Module: Gitlab::Database::MigrationHelpers

Includes:
AsyncConstraints::MigrationHelpers, AsyncIndexes::MigrationHelpers, DynamicModelHelpers, FeatureFlagMigratorHelpers, WraparoundVacuumHelpers, Gitlab::Database::Migrations::BatchedBackgroundMigrationHelpers, Gitlab::Database::Migrations::ConstraintsHelpers, Gitlab::Database::Migrations::ExtensionHelpers, Gitlab::Database::Migrations::ForeignKeyHelpers, Gitlab::Database::Migrations::LockRetriesHelpers, Gitlab::Database::Migrations::RedisHelpers, Gitlab::Database::Migrations::ReestablishedConnectionStack, Gitlab::Database::Migrations::SidekiqHelpers, Gitlab::Database::Migrations::TimeoutHelpers, PartitionHelpers, RenameTableHelpers
Included in:
CascadingNamespaceSettings, V2, WorkItems::Widgets, PartitioningMigrationHelpers::IndexHelpers, PartitioningMigrationHelpers::TableManagementHelpers, PartitioningMigrationHelpers::UniquenessHelpers
Defined in:
lib/gitlab/database/migration_helpers.rb,
lib/gitlab/database/migration_helpers/v2.rb,
lib/gitlab/database/migration_helpers/swapping.rb,
lib/gitlab/database/migration_helpers/announce_database.rb,
lib/gitlab/database/migration_helpers/convert_to_bigint.rb,
lib/gitlab/database/migration_helpers/work_items/widgets.rb,
lib/gitlab/database/migration_helpers/wraparound_autovacuum.rb,
lib/gitlab/database/migration_helpers/restrict_gitlab_schema.rb,
lib/gitlab/database/migration_helpers/loose_foreign_key_helpers.rb,
lib/gitlab/database/migration_helpers/wraparound_vacuum_helpers.rb,
lib/gitlab/database/migration_helpers/cascading_namespace_settings.rb,
lib/gitlab/database/migration_helpers/feature_flag_migrator_helpers.rb,
lib/gitlab/database/migration_helpers/automatic_lock_writes_on_tables.rb,
lib/gitlab/database/migration_helpers/require_disable_ddl_transaction_for_multiple_locks.rb

Defined Under Namespace

Modules: AnnounceDatabase, AutomaticLockWritesOnTables, CascadingNamespaceSettings, ConvertToBigint, FeatureFlagMigratorHelpers, LooseForeignKeyHelpers, RequireDisableDdlTransactionForMultipleLocks, RestrictGitlabSchema, Swapping, V2, WorkItems, WraparoundAutovacuum, WraparoundVacuumHelpers

Constant Summary collapse

INTEGER_IDS_YET_TO_INITIALIZED_TO_BIGINT_FILE_PATH = 
'db/integer_ids_not_yet_initialized_to_bigint.yml'
TABLE_INT_IDS_YAML_FILE_COMMENT = 
<<-MESSAGE.strip_heredoc
  # -- DON'T MANUALLY EDIT --
  # Contains the list of integer IDs which were converted to bigint for new installations in
  # https://gitlab.com/gitlab-org/gitlab/-/issues/438124, but they are still integers for existing instances.
  # On initialize_conversion_of_integer_to_bigint those integer IDs will be removed automatically from here.
MESSAGE
PENDING_INT_IDS_ERROR_MSG = 
"'%{table}' table still has %{int_ids} integer IDs. "\
"Please include them in the 'columns' param and in your backfill migration. "\
"For more info: https://gitlab.com/gitlab-org/gitlab/-/issues/482470"
ENFORCE_INITIALIZE_ALL_INT_IDS_FROM_MILESTONE = 
'17.4'
DEFAULT_TIMESTAMP_COLUMNS = 
%i[created_at updated_at].freeze

Constants included from DynamicModelHelpers

DynamicModelHelpers::BATCH_SIZE

Constants included from Gitlab::Database::Migrations::RedisHelpers

Gitlab::Database::Migrations::RedisHelpers::SCAN_START_CURSOR

Constants included from Gitlab::Database::Migrations::SidekiqHelpers

Gitlab::Database::Migrations::SidekiqHelpers::DEFAULT_MAX_ATTEMPTS, Gitlab::Database::Migrations::SidekiqHelpers::DEFAULT_TIMES_IN_A_ROW

Constants included from Gitlab::Database::Migrations::ConstraintsHelpers

Gitlab::Database::Migrations::ConstraintsHelpers::MAX_IDENTIFIER_NAME_LENGTH

Constants included from Gitlab::Database::Migrations::BatchedBackgroundMigrationHelpers

Gitlab::Database::Migrations::BatchedBackgroundMigrationHelpers::BATCH_CLASS_NAME, Gitlab::Database::Migrations::BatchedBackgroundMigrationHelpers::BATCH_MIN_DELAY, Gitlab::Database::Migrations::BatchedBackgroundMigrationHelpers::BATCH_MIN_VALUE, Gitlab::Database::Migrations::BatchedBackgroundMigrationHelpers::BATCH_SIZE, Gitlab::Database::Migrations::BatchedBackgroundMigrationHelpers::EARLY_FINALIZATION_ERROR, Gitlab::Database::Migrations::BatchedBackgroundMigrationHelpers::ENFORCE_EARLY_FINALIZATION_FROM_VERSION, Gitlab::Database::Migrations::BatchedBackgroundMigrationHelpers::MIGRATION_NOT_FOUND_MESSAGE, Gitlab::Database::Migrations::BatchedBackgroundMigrationHelpers::MINIMUM_PAUSE_MS, Gitlab::Database::Migrations::BatchedBackgroundMigrationHelpers::NonExistentMigrationError, Gitlab::Database::Migrations::BatchedBackgroundMigrationHelpers::SUB_BATCH_SIZE

Instance Method Summary collapse

Methods included from PartitionHelpers

#partition?, #table_partitioned?

Methods included from WraparoundVacuumHelpers

#check_if_wraparound_in_progress

Methods included from AsyncConstraints::MigrationHelpers

#prepare_async_check_constraint_validation, #prepare_async_foreign_key_validation, #prepare_partitioned_async_check_constraint_validation, #prepare_partitioned_async_foreign_key_validation, #unprepare_async_check_constraint_validation, #unprepare_async_foreign_key_validation, #unprepare_partitioned_async_check_constraint_validation, #unprepare_partitioned_async_foreign_key_validation

Methods included from AsyncIndexes::MigrationHelpers

#async_index_creation_available?, #prepare_async_index, #prepare_async_index_from_sql, #prepare_async_index_removal, #unprepare_async_index, #unprepare_async_index_by_name

Methods included from RenameTableHelpers

#finalize_table_rename, #rename_table_safely, #undo_finalize_table_rename, #undo_rename_table_safely

Methods included from FeatureFlagMigratorHelpers

#down_migrate_to_jsonb_setting, #down_migrate_to_setting, #up_migrate_to_jsonb_setting, #up_migrate_to_setting

Methods included from DynamicModelHelpers

define_batchable_model

Methods included from Gitlab::Database::Migrations::ForeignKeyHelpers

#add_concurrent_foreign_key, #concurrent_foreign_key_name, #foreign_key_exists?, #remove_foreign_key_if_exists, #remove_foreign_key_without_error, #validate_foreign_key

Methods included from Gitlab::Database::Migrations::LockRetriesHelpers

#with_lock_retries

Methods included from Gitlab::Database::Migrations::TimeoutHelpers

#disable_statement_timeout

Methods included from Gitlab::Database::Migrations::RedisHelpers

#queue_redis_migration_job

Methods included from Gitlab::Database::Migrations::SidekiqHelpers

#migrate_across_instance, #migrate_within_instance, #sidekiq_queue_migrate, #sidekiq_remove_jobs

Methods included from Gitlab::Database::Migrations::ExtensionHelpers

#create_extension, #drop_extension

Methods included from Gitlab::Database::Migrations::ConstraintsHelpers

#add_check_constraint, #add_multi_column_not_null_constraint, #add_not_null_constraint, #add_text_limit, #check_constraint_exists?, check_constraint_exists?, #check_constraint_name, #check_not_null_constraint_exists?, #check_text_limit_exists?, #copy_check_constraints, #drop_constraint, #remove_check_constraint, #remove_multi_column_not_null_constraint, #remove_not_null_constraint, #remove_text_limit, #rename_constraint, #switch_constraint_names, #text_limit_name, #validate_check_constraint, #validate_multi_column_not_null_constraint, #validate_not_null_constraint, #validate_text_limit

Methods included from Gitlab::Database::Migrations::BatchedBackgroundMigrationHelpers

#delete_batched_background_migration, #ensure_batched_background_migration_is_finished, #finalize_batched_background_migration, #gitlab_schema_from_context, #queue_batched_background_migration

Methods included from Gitlab::Database::Migrations::ReestablishedConnectionStack

#with_restored_connection_stack

Instance Method Details

#add_concurrent_index(table_name, column_name, options = {}) ⇒ Object

Creates a new index, concurrently

Example:

add_concurrent_index :users, :some_column

See Rails’ ‘add_index` for more info on the available arguments.



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# File 'lib/gitlab/database/migration_helpers.rb', line 113

def add_concurrent_index(table_name, column_name, options = {})
  if transaction_open?
    raise 'add_concurrent_index can not be run inside a transaction, ' \
      'you can disable transactions by calling disable_ddl_transaction! ' \
      'in the body of your migration class'
  end

  if !options.delete(:allow_partition) && partition?(table_name)
    raise ArgumentError, 'add_concurrent_index can not be used on a partitioned '  \
      'table. Please use add_concurrent_partitioned_index on the partitioned table ' \
      'as we need to create indexes on each partition and an index on the parent table'
  end

  options = options.merge({ algorithm: :concurrently })

  if index_exists?(table_name, column_name, **options)
    name = options[:name] || index_name(table_name, column_name)
    _, schema = table_name.to_s.split('.').reverse

    if index_invalid?(name, schema: schema)
      say "Index being recreated because the existing version was INVALID: table_name: #{table_name}, column_name: #{column_name}"

      remove_concurrent_index_by_name(table_name, name)
    else
      say "Index not created because it already exists (this may be due to an aborted migration or similar): table_name: #{table_name}, column_name: #{column_name}"

      return
    end
  end

  disable_statement_timeout do
    add_index(table_name, column_name, **options)
  end

  # We created this index. Now let's remove the queuing entry for async creation in case it's still there.
  unprepare_async_index(table_name, column_name, **options)
end

#add_primary_key_using_index(table_name, pk_name, index_to_use) ⇒ Object 



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# File 'lib/gitlab/database/migration_helpers.rb', line 923

def add_primary_key_using_index(table_name, pk_name, index_to_use)
  execute <<~SQL
    ALTER TABLE #{quote_table_name(table_name)} ADD CONSTRAINT #{quote_table_name(pk_name)} PRIMARY KEY USING INDEX #{quote_table_name(index_to_use)}
  SQL
end

#add_sequence(table_name, column_name, sequence_name, start_value) ⇒ Object 



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# File 'lib/gitlab/database/migration_helpers.rb', line 944

def add_sequence(table_name, column_name, sequence_name, start_value)
  execute <<~SQL
    CREATE SEQUENCE #{quote_table_name(sequence_name)} START #{start_value};
    ALTER TABLE #{quote_table_name(table_name)} ALTER COLUMN #{quote_column_name(column_name)} SET DEFAULT nextval(#{quote(sequence_name)})
  SQL
end

#add_timestamps_with_timezone(table_name, options = {}) ⇒ Object

Adds ‘created_at` and `updated_at` columns with timezone information.

This method is an improved version of Rails’ built-in method ‘add_timestamps`.

By default, adds ‘created_at` and `updated_at` columns, but these can be specified as:

add_timestamps_with_timezone(:my_table, columns: [:created_at, :deleted_at])

This allows you to create just the timestamps you need, saving space.

Available options are:

:default - The default value for the column.
:null - When set to `true` the column will allow NULL values.
      The default is to not allow NULL values.
:columns - the column names to create. Must end with `_at`.
           Default value: `DEFAULT_TIMESTAMP_COLUMNS`

All options are optional.



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# File 'lib/gitlab/database/migration_helpers.rb', line 75

def add_timestamps_with_timezone(table_name, options = {})
  columns = options.fetch(:columns, DEFAULT_TIMESTAMP_COLUMNS)

  columns.each do |column_name|
    validate_timestamp_column_name!(column_name)

    add_column(
      table_name,
      column_name,
      :datetime_with_timezone,
      default: options[:default],
      null: options[:null] || false
    )
  end
end

#backfill_conversion_of_integer_to_bigint(table, columns, primary_key: :id, batch_size: 20_000, sub_batch_size: 1000, pause_ms: 100, interval: 2.minutes) ⇒ Object

Backfills the new columns used in an integer-to-bigint conversion using background migrations.

  • This helper should be called from a post-deployment migration.

  • In order for this helper to work properly, the new columns must be first initialized with the ‘initialize_conversion_of_integer_to_bigint` helper.

  • It tracks the scheduled background jobs through Gitlab::Database::BackgroundMigration::BatchedMigration, which allows a more thorough check that all jobs succeeded in the cleanup migration and is way faster for very large tables.

    Note: this helper is intended to be used in a post-deployment migration, to ensure any new code is deployed (including background job changes) before we begin processing the background migration.

    This helper is part 2 of a multi-step migration process:

    1. initialize_conversion_of_integer_to_bigint to create the new columns and database trigger

    2. backfill_conversion_of_integer_to_bigint to copy historic data using background migrations

    3. remaining steps TBD, see #288005

table - The name of the database table containing the column columns - The name, or an array of names, of the column(s) we want to convert to bigint. primary_key - The name of the primary key column (most often :id) batch_size - The number of rows to schedule in a single background migration sub_batch_size - The smaller batches that will be used by each scheduled job

to update the table. Useful to keep each update at ~100ms while executing
more updates per interval (2.minutes)
Note that each execution of a sub-batch adds a constant 100ms sleep
 time in between the updates, which must be taken into account
 while calculating the batch, sub_batch and interval values.

interval - The time interval between every background migration

example: Assume that we have figured out that updating 200 records of the events

table takes ~100ms on average.

We can set the sub_batch_size to 200, leave the interval to the default

and set the batch_size to 50_000 which will require
~50s = (50000 / 200) * (0.1 + 0.1) to complete and leaves breathing space
between the scheduled jobs



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# File 'lib/gitlab/database/migration_helpers.rb', line 702

def backfill_conversion_of_integer_to_bigint(
  table,
  columns,
  primary_key: :id,
  batch_size: 20_000,
  sub_batch_size: 1000,
  pause_ms: 100,
  interval: 2.minutes
)
  Gitlab::Database::Migrations::Conversions::BigintConverter
    .new(self, table, columns)
    .backfill(
      primary_key: primary_key,
      batch_size: batch_size,
      sub_batch_size: sub_batch_size,
      pause_ms: pause_ms,
      job_interval: interval
    )
end

#backfill_iids(table) ⇒ Object

Note this should only be used with very small tables



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# File 'lib/gitlab/database/migration_helpers.rb', line 910

def backfill_iids(table)
  sql = <<-END
    UPDATE #{table}
    SET iid = #{table}_with_calculated_iid.iid_num
    FROM (
      SELECT id, ROW_NUMBER() OVER (PARTITION BY project_id ORDER BY id ASC) AS iid_num FROM #{table}
    ) AS #{table}_with_calculated_iid
    WHERE #{table}.id = #{table}_with_calculated_iid.id
  END

  execute(sql)
end

#change_column_type_concurrently(table, column, new_type, type_cast_function: nil, batch_column_name: :id) ⇒ Object

Changes the type of a column concurrently.

table - The table containing the column. column - The name of the column to change. new_type - The new column type.



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# File 'lib/gitlab/database/migration_helpers.rb', line 456

def change_column_type_concurrently(table, column, new_type, type_cast_function: nil, batch_column_name: :id)
  temp_column = "#{column}_for_type_change"

  rename_column_concurrently(table, column, temp_column, type: new_type, type_cast_function: type_cast_function, batch_column_name: batch_column_name)
end

#check_trigger_permissions!(table) ⇒ Object 



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# File 'lib/gitlab/database/migration_helpers.rb', line 843

def check_trigger_permissions!(table)
  unless Grant.create_and_execute_trigger?(table)
    dbname = ApplicationRecord.database.database_name
    user = ApplicationRecord.database.username

    raise <<-EOF
Your database user is not allowed to create, drop, or execute triggers on the
table #{table}.

If you are using PostgreSQL you can solve this by logging in to the GitLab
database (#{dbname}) using a super user and running:

    ALTER #{user} WITH SUPERUSER

This query will grant the user super user permissions, ensuring you don't run
into similar problems in the future (e.g. when new tables are created).
    EOF
  end
end

#cleanup_concurrent_column_rename(table, old, new) ⇒ Object

Cleans up a concurrent column name.

This method takes care of removing previously installed triggers as well as removing the old column.

table - The name of the database table. old - The name of the old column. new - The name of the new column.



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# File 'lib/gitlab/database/migration_helpers.rb', line 558

def cleanup_concurrent_column_rename(table, old, new)
  trigger_name = rename_trigger_name(table, old, new)

  check_trigger_permissions!(table)

  remove_rename_triggers(table, trigger_name)

  remove_column(table, old)
end

#cleanup_concurrent_column_type_change(table, column, temp_column: nil) ⇒ Object

Performs cleanup of a concurrent type change.

table - The table containing the column. column - The name of the column to change. new_type - The new column type.



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# File 'lib/gitlab/database/migration_helpers.rb', line 477

def cleanup_concurrent_column_type_change(table, column, temp_column: nil)
  temp_column ||= "#{column}_for_type_change"

  transaction do
    # This has to be performed in a transaction as otherwise we might have
    # inconsistent data.
    cleanup_concurrent_column_rename(table, column, temp_column)
    rename_column(table, temp_column, column)
  end
end

#cleanup_conversion_of_integer_to_bigint(table, columns) ⇒ Object

Similar to ‘revert_initialize_conversion_of_integer_to_bigint`, but `cleanup_conversion_of_integer_to_bigint` updates the yaml file



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# File 'lib/gitlab/database/migration_helpers.rb', line 649

def cleanup_conversion_of_integer_to_bigint(table, columns)
  Gitlab::Database::Migrations::Conversions::BigintConverter
    .new(self, table, columns)
    .cleanup
end

#column_for(table, name) ⇒ Object

Returns the column for the given table and column name.



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# File 'lib/gitlab/database/migration_helpers.rb', line 821

def column_for(table, name)
  name = name.to_s

  column = columns(table).find { |column| column.name == name }
  raise(missing_schema_object_message(table, "column", name)) if column.nil?

  column
end

#convert_to_bigint_column(column) ⇒ Object 



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# File 'lib/gitlab/database/migration_helpers.rb', line 602

def convert_to_bigint_column(column)
  "#{column}_convert_to_bigint"
end

#convert_to_type_column(column, from_type, to_type) ⇒ Object 



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# File 'lib/gitlab/database/migration_helpers.rb', line 598

def convert_to_type_column(column, from_type, to_type)
  "#{column}_convert_#{from_type}_to_#{to_type}"
end

#copy_foreign_keys(table, old, new) ⇒ Object

Copies all foreign keys for the old column to the new column.

table - The table containing the columns and indexes. old - The old column. new - The new column.



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# File 'lib/gitlab/database/migration_helpers.rb', line 811

def copy_foreign_keys(table, old, new)
  foreign_keys_for(table, old).each do |fk|
    add_concurrent_foreign_key(fk.from_table,
      fk.to_table,
      column: new,
      on_delete: fk.on_delete)
  end
end

#copy_indexes(table, old, new) ⇒ Object

Copies all indexes for the old column to a new column.

table - The table containing the columns and indexes. old - The old column. new - The new column.



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# File 'lib/gitlab/database/migration_helpers.rb', line 759

def copy_indexes(table, old, new)
  old = old.to_s
  new = new.to_s

  indexes_for(table, old).each do |index|
    new_columns = index.columns.map do |column|
      column == old ? new : column
    end

    # This is necessary as we can't properly rename indexes such as
    # "ci_taggings_idx".
    unless index.name.include?(old)
      raise "The index #{index.name} can not be copied as it does not "\
        "mention the old column. You have to rename this index manually first."
    end

    name = index.name.gsub(old, new)

    if name.length > 63
      digest = Digest::SHA256.hexdigest(name).first(10)
      name = "idx_copy_#{digest}"
    end

    options = {
      unique: index.unique,
      name: name,
      length: index.lengths,
      order: index.orders
    }

    options[:using] = index.using if index.using
    options[:where] = index.where if index.where

    unless index.opclasses.blank?
      opclasses = index.opclasses.dup

      # Copy the operator classes for the old column (if any) to the new
      # column.
      opclasses[new] = opclasses.delete(old) if opclasses[old]

      options[:opclass] = opclasses
    end

    add_concurrent_index(table, new_columns, options)
  end
end

#create_or_update_plan_limit(limit_name, plan_name, limit_value) ⇒ Object 



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# File 'lib/gitlab/database/migration_helpers.rb', line 895

def create_or_update_plan_limit(limit_name, plan_name, limit_value)
  limit_name_quoted = quote_column_name(limit_name)
  plan_name_quoted = quote(plan_name)
  limit_value_quoted = quote(limit_value)

  ::Gitlab::Database.allow_cross_joins_across_databases(url: 'https://gitlab.com/gitlab-org/gitlab/-/issues/519892') do
    execute <<~SQL
      INSERT INTO plan_limits (plan_id, #{limit_name_quoted})
      SELECT id, #{limit_value_quoted} FROM plans WHERE name = #{plan_name_quoted} LIMIT 1
      ON CONFLICT (plan_id) DO UPDATE SET #{limit_name_quoted} = EXCLUDED.#{limit_name_quoted};
    SQL
  end
end

#define_batchable_model(table_name, connection: self.connection, primary_key: nil, base_class: ActiveRecord::Base) ⇒ Object 



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# File 'lib/gitlab/database/migration_helpers.rb', line 40

def define_batchable_model(
  table_name,
  connection: self.connection,
  primary_key: nil,
  base_class: ActiveRecord::Base
)
  super
end

#drop_sequence(table_name, column_name, sequence_name) ⇒ Object 



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# File 'lib/gitlab/database/migration_helpers.rb', line 937

def drop_sequence(table_name, column_name, sequence_name)
  execute <<~SQL
    ALTER TABLE #{quote_table_name(table_name)} ALTER COLUMN #{quote_column_name(column_name)} DROP DEFAULT;
    DROP SEQUENCE IF EXISTS #{quote_table_name(sequence_name)}
  SQL
end

#each_batch(table_name, connection: self.connection, **kwargs) ⇒ Object 



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# File 'lib/gitlab/database/migration_helpers.rb', line 49

def each_batch(table_name, connection: self.connection, **kwargs)
  super(table_name, connection: connection, **kwargs)
end

#each_batch_range(table_name, connection: self.connection, **kwargs) ⇒ Object 



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# File 'lib/gitlab/database/migration_helpers.rb', line 53

def each_batch_range(table_name, connection: self.connection, **kwargs)
  super(table_name, connection: connection, **kwargs)
end

#ensure_backfill_conversion_of_integer_to_bigint_is_finished(table, columns, primary_key: :id) ⇒ Object

Handy helper to ensure data finalization for bigint conversion process



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# File 'lib/gitlab/database/migration_helpers.rb', line 723

def ensure_backfill_conversion_of_integer_to_bigint_is_finished(table, columns, primary_key: :id)
  Gitlab::Database::Migrations::Conversions::BigintConverter
    .new(self, table, columns)
    .ensure_backfill(primary_key: primary_key)
end

#false_value ⇒ Object 



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# File 'lib/gitlab/database/migration_helpers.rb', line 246

def false_value
  Database.false_value
end

#foreign_keys_for(table, column) ⇒ Object

Returns an Array containing the foreign keys for the given column.



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# File 'lib/gitlab/database/migration_helpers.rb', line 748

def foreign_keys_for(table, column)
  column = column.to_s

  foreign_keys(table).select { |fk| fk.column == column }
end

#index_exists_by_name?(table, index) ⇒ Boolean

Fetches indexes on a column by name for postgres.

This will include indexes using an expression on the column, for example: ‘CREATE INDEX CONCURRENTLY index_name ON table (LOWER(column));`

We can remove this when upgrading to Rails 5 with an updated ‘index_exists?`:

Or this can be removed when we no longer support postgres < 9.5, so we can use ‘CREATE INDEX IF NOT EXISTS`.

Returns:

  • (Boolean) 


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# File 'lib/gitlab/database/migration_helpers.rb', line 873

def index_exists_by_name?(table, index)
  # We can't fall back to the normal `index_exists?` method because that
  # does not find indexes without passing a column name.
  if indexes(table).map(&:name).include?(index.to_s)
    true
  else
    postgres_exists_by_name?(table, index)
  end
end

#index_invalid?(index_name, schema: nil) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/gitlab/database/migration_helpers.rb', line 151

def index_invalid?(index_name, schema: nil)
  index_name = connection.quote(index_name)
  schema = connection.quote(schema) if schema
  schema ||= 'current_schema()'

  connection.select_value(<<~SQL)
    select not i.indisvalid
    from pg_class c
    inner join pg_index i
      on c.oid = i.indexrelid
    inner join pg_namespace n
      on n.oid = c.relnamespace
    where n.nspname = #{schema}
      and c.relname = #{index_name}
  SQL
end

#indexes_for(table, column) ⇒ Object

Returns an Array containing the indexes for the given column



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# File 'lib/gitlab/database/migration_helpers.rb', line 741

def indexes_for(table, column)
  column = column.to_s

  indexes(table).select { |index| index.columns.include?(column) }
end

#initialize_conversion_of_integer_to_bigint(table, columns, primary_key: :id) ⇒ Object

Initializes the conversion of a set of integer columns to bigint

It can be used for converting both a Primary Key and any Foreign Keys that may reference it or any other integer column that we may want to upgrade (e.g. columns that store IDs, but are not set as FKs).

  • For primary keys and Foreign Keys (or other columns) defined as NOT NULL,

    the new bigint column is added with a hardcoded NOT NULL DEFAULT 0
which allows us to skip a very costly verification step once we
are ready to switch it.

    This is crucial for Primary Key conversions, because setting a column

    as the PK converts even check constraints to NOT NULL constraints
and forces an inline re-verification of the whole table.

  • It sets up a trigger to keep the two columns in sync.

    Note: this helper is intended to be used in a regular (pre-deployment) migration.

    This helper is part 1 of a multi-step migration process:

    1. initialize_conversion_of_integer_to_bigint to create the new columns and database trigger

    2. backfill_conversion_of_integer_to_bigint to copy historic data using background migrations

    3. remaining steps TBD, see #288005

table - The name of the database table containing the column columns - The name, or array of names, of the column(s) that we want to convert to bigint. primary_key - The name of the primary key column (most often :id)



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# File 'lib/gitlab/database/migration_helpers.rb', line 631

def initialize_conversion_of_integer_to_bigint(table, columns, primary_key: :id) # rubocop:disable Lint/UnusedMethodArgument -- for backward compatibility, don't remove primary_key
  Gitlab::Database::Migrations::Conversions::BigintConverter
    .new(self, table, columns)
    .init
end

#install_rename_triggers(table, old, new, trigger_name: nil) ⇒ Object

Installs triggers in a table that keep a new column in sync with an old one.

table - The name of the table to install the trigger in. old_column - The name of the old column. new_column - The name of the new column. trigger_name - The name of the trigger to use (optional).



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# File 'lib/gitlab/database/migration_helpers.rb', line 415

def install_rename_triggers(table, old, new, trigger_name: nil)
  Gitlab::Database::UnidirectionalCopyTrigger.on_table(table, connection: connection).create(old, new, trigger_name: trigger_name)
end

#install_sharding_key_assignment_trigger(**args) ⇒ Object

Installs a trigger in a table that assigns a sharding key from an associated table.

table: The table to install the trigger in. sharding_key: The column to be assigned on ‘table`. parent_table: The associated table with the sharding key to be copied. parent_sharding_key: The sharding key on the parent table that will be copied to `sharding_key` on `table`. foreign_key: The column used to fetch the relevant record from `parent_table`.



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# File 'lib/gitlab/database/migration_helpers.rb', line 436

def install_sharding_key_assignment_trigger(**args)
  Gitlab::Database::Triggers::AssignDesiredShardingKey.new(**args.merge(connection: connection)).create
end

#lock_tables(*tables, mode: :access_exclusive, only: nil, nowait: nil) ⇒ Object 



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# File 'lib/gitlab/database/migration_helpers.rb', line 964

def lock_tables(*tables, mode: :access_exclusive, only: nil, nowait: nil)
  only_param = only && 'ONLY'
  nowait_param = nowait && 'NOWAIT'
  tables_param = tables.map { |t| quote_table_name(t) }.join(', ')
  mode_param = mode.to_s.upcase.tr('_', ' ')

  execute(<<~SQL.squish)
    LOCK TABLE #{only_param} #{tables_param} IN #{mode_param} MODE #{nowait_param}
  SQL
end

#postgres_exists_by_name?(table, name) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/gitlab/database/migration_helpers.rb', line 883

def postgres_exists_by_name?(table, name)
  index_sql = <<~SQL
    SELECT COUNT(*)
    FROM pg_catalog.pg_indexes
    WHERE schemaname = #{connection.quote(current_schema)}
      AND tablename = #{connection.quote(table)}
      AND indexname = #{connection.quote(name)}
  SQL

  connection.select_value(index_sql).to_i > 0
end

#remove_column_default(table_name, column_name) ⇒ Object

While it is safe to call ‘change_column_default` on a column without default it would still require access exclusive lock on the table and for tables with high autovacuum(wraparound prevention) it will fail if their executions overlap.



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# File 'lib/gitlab/database/migration_helpers.rb', line 956

def remove_column_default(table_name, column_name)
  column = connection.columns(table_name).find { |col| col.name == column_name.to_s }

  if column.default || column.default_function
    change_column_default(table_name, column_name, to: nil)
  end
end

#remove_concurrent_index(table_name, column_name, options = {}) ⇒ Object

Removes an existed index, concurrently

Example:

remove_concurrent_index :users, :some_column

See Rails’ ‘remove_index` for more info on the available arguments.



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# File 'lib/gitlab/database/migration_helpers.rb', line 175

def remove_concurrent_index(table_name, column_name, options = {})
  if transaction_open?
    raise 'remove_concurrent_index can not be run inside a transaction, ' \
      'you can disable transactions by calling disable_ddl_transaction! ' \
      'in the body of your migration class'
  end

  if partition?(table_name)
    raise ArgumentError, 'remove_concurrent_index can not be used on a partitioned '  \
      'table. Please use remove_concurrent_partitioned_index_by_name on the partitioned table ' \
      'as we need to remove the index on the parent table'
  end

  options = options.merge({ algorithm: :concurrently })

  unless index_exists?(table_name, column_name, **options)
    Gitlab::AppLogger.warn "Index not removed because it does not exist (this may be due to an aborted migration or similar): table_name: #{table_name}, column_name: #{column_name}"
    return
  end

  disable_statement_timeout do
    remove_index(table_name, **options.merge({ column: column_name }))
  end

  # We removed this index. Now let's make sure it's not queued for async creation.
  unprepare_async_index(table_name, column_name, **options)
end

#remove_concurrent_index_by_name(table_name, index_name, options = {}) ⇒ Object

Removes an existing index, concurrently

Example:

remove_concurrent_index :users, "index_X_by_Y"

See Rails’ ‘remove_index` for more info on the available arguments.



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# File 'lib/gitlab/database/migration_helpers.rb', line 210

def remove_concurrent_index_by_name(table_name, index_name, options = {})
  if transaction_open?
    raise 'remove_concurrent_index_by_name can not be run inside a transaction, ' \
      'you can disable transactions by calling disable_ddl_transaction! ' \
      'in the body of your migration class'
  end

  if partition?(table_name)
    raise ArgumentError, 'remove_concurrent_index_by_name can not be used on a partitioned '  \
      'table. Please use remove_concurrent_partitioned_index_by_name on the partitioned table ' \
      'as we need to remove the index on the parent table'
  end

  index_name = index_name[:name] if index_name.is_a?(Hash)

  raise 'remove_concurrent_index_by_name must get an index name as the second argument' if index_name.blank?

  options = options.merge({ algorithm: :concurrently })

  unless index_exists_by_name?(table_name, index_name)
    Gitlab::AppLogger.warn "Index not removed because it does not exist (this may be due to an aborted migration or similar): table_name: #{table_name}, index_name: #{index_name}"
    return
  end

  disable_statement_timeout do
    remove_index(table_name, **options.merge({ name: index_name }))
  end

  # We removed this index. Now let's make sure it's not queued for async creation.
  unprepare_async_index_by_name(table_name, index_name, **options)
end

#remove_rename_triggers(table, trigger) ⇒ Object

Removes the triggers used for renaming a column concurrently.



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# File 'lib/gitlab/database/migration_helpers.rb', line 420

def remove_rename_triggers(table, trigger)
  Gitlab::Database::UnidirectionalCopyTrigger.on_table(table, connection: connection).drop(trigger)
end

#remove_sharding_key_assignment_trigger(**args) ⇒ Object

Removes trigger used for assigning sharding keys.

table: The table to install the trigger in. sharding_key: The column to be assigned on ‘table`. parent_table: The associated table with the sharding key to be copied. parent_sharding_key: The sharding key on the parent table that will be copied to `sharding_key` on `table`. foreign_key: The column used to fetch the relevant record from `parent_table`.



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# File 'lib/gitlab/database/migration_helpers.rb', line 447

def remove_sharding_key_assignment_trigger(**args)
  Gitlab::Database::Triggers::AssignDesiredShardingKey.new(**args.merge(connection: connection)).drop
end

#remove_timestamps(table_name, options = {}) ⇒ Object

To be used in the ‘#down` method of migrations that use `#add_timestamps_with_timezone`.

Available options are:

:columns - the column names to remove. Must be one
           Default value: `DEFAULT_TIMESTAMP_COLUMNS`

All options are optional.



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# File 'lib/gitlab/database/migration_helpers.rb', line 99

def remove_timestamps(table_name, options = {})
  columns = options.fetch(:columns, DEFAULT_TIMESTAMP_COLUMNS)
  columns.each do |column_name|
    remove_column(table_name, column_name)
  end
end

#rename_column_concurrently(table, old, new, type: nil, type_cast_function: nil, batch_column_name: :id) ⇒ Object

Renames a column without requiring downtime.

Concurrent renames work by using database triggers to ensure both the old and new column are in sync. However, this method will not remove the triggers or the old column automatically; this needs to be done manually in a post-deployment migration. This can be done using the method ‘cleanup_concurrent_column_rename`.

table - The name of the database table containing the column. old - The old column name. new - The new column name. type - The type of the new column. If no type is given the old column’s

type is used.

batch_column_name - option is for tables without primary key, in this

case another unique integer column can be used. Example: :user_id



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# File 'lib/gitlab/database/migration_helpers.rb', line 374

def rename_column_concurrently(table, old, new, type: nil, type_cast_function: nil, batch_column_name: :id)
  unless column_exists?(table, batch_column_name)
    raise "Column #{batch_column_name} does not exist on #{table}"
  end

  if transaction_open?
    raise 'rename_column_concurrently can not be run inside a transaction'
  end

  check_trigger_permissions!(table)

  create_column_from(table, old, new, type: type, batch_column_name: batch_column_name, type_cast_function: type_cast_function)

  install_rename_triggers(table, old, new)
end

#rename_trigger_name(table, old, new) ⇒ Object

Returns the (base) name to use for triggers when renaming columns.



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# File 'lib/gitlab/database/migration_helpers.rb', line 425

def rename_trigger_name(table, old, new)
  Gitlab::Database::UnidirectionalCopyTrigger.on_table(table, connection: connection).name(old, new)
end

#replace_sql(column, pattern, replacement) ⇒ Object

This will replace the first occurrence of a string in a column with the replacement using ‘regexp_replace`



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# File 'lib/gitlab/database/migration_helpers.rb', line 832

def replace_sql(column, pattern, replacement)
  quoted_pattern = Arel::Nodes::Quoted.new(pattern.to_s)
  quoted_replacement = Arel::Nodes::Quoted.new(replacement.to_s)

  replace = Arel::Nodes::NamedFunction.new(
    "regexp_replace", [column, quoted_pattern, quoted_replacement]
  )

  Arel::Nodes::SqlLiteral.new(replace.to_sql)
end

#restore_conversion_of_integer_to_bigint(table, columns, primary_key: :id) ⇒ Object

Reverts ‘cleanup_conversion_of_integer_to_bigint`

table - The name of the database table containing the columns columns - The name, or array of names, of the column(s) that we have converted to bigint. primary_key - The name of the primary key column (most often :id)



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# File 'lib/gitlab/database/migration_helpers.rb', line 660

def restore_conversion_of_integer_to_bigint(table, columns, primary_key: :id) # rubocop:disable Lint/UnusedMethodArgument -- for backward compatibility, don't remove primary_key
  Gitlab::Database::Migrations::Conversions::BigintConverter
    .new(self, table, columns)
    .restore_cleanup
end

#revert_backfill_conversion_of_integer_to_bigint(table, columns, primary_key: :id) ⇒ Object

Reverts ‘backfill_conversion_of_integer_to_bigint`

table - The name of the database table containing the column columns - The name, or an array of names, of the column(s) we want to convert to bigint. primary_key - The name of the primary key column (most often :id)



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# File 'lib/gitlab/database/migration_helpers.rb', line 734

def revert_backfill_conversion_of_integer_to_bigint(table, columns, primary_key: :id)
  Gitlab::Database::Migrations::Conversions::BigintConverter
    .new(self, table, columns)
    .revert_backfill(primary_key: primary_key)
end

#revert_initialize_conversion_of_integer_to_bigint(table, columns) ⇒ Object

Reverts ‘initialize_conversion_of_integer_to_bigint`

table - The name of the database table containing the columns columns - The name, or array of names, of the column(s) that we’re converting to bigint.



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# File 'lib/gitlab/database/migration_helpers.rb', line 641

def revert_initialize_conversion_of_integer_to_bigint(table, columns)
  Gitlab::Database::Migrations::Conversions::BigintConverter
    .new(self, table, columns)
    .revert_init
end

#swap_primary_key(table_name, primary_key_name, index_to_use) ⇒ Object Also known as: unswap_primary_key 



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# File 'lib/gitlab/database/migration_helpers.rb', line 929

def swap_primary_key(table_name, primary_key_name, index_to_use)
  with_lock_retries(raise_on_exhaustion: true) do
    drop_constraint(table_name, primary_key_name, cascade: true)
    add_primary_key_using_index(table_name, primary_key_name, index_to_use)
  end
end

#table_integer_ids ⇒ Object 



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# File 'lib/gitlab/database/migration_helpers.rb', line 975

def table_integer_ids
  YAML.safe_load_file(File.join(INTEGER_IDS_YET_TO_INITIALIZED_TO_BIGINT_FILE_PATH))
end

#true_value ⇒ Object 



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# File 'lib/gitlab/database/migration_helpers.rb', line 242

def true_value
  Database.true_value
end

#undo_change_column_type_concurrently(table, column) ⇒ Object

Reverses operations performed by change_column_type_concurrently.

table - The table containing the column. column - The name of the column to change.



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# File 'lib/gitlab/database/migration_helpers.rb', line 466

def undo_change_column_type_concurrently(table, column)
  temp_column = "#{column}_for_type_change"

  undo_rename_column_concurrently(table, column, temp_column)
end

#undo_cleanup_concurrent_column_rename(table, old, new, type: nil, batch_column_name: :id) ⇒ Object

Reverses the operations performed by cleanup_concurrent_column_rename.

This method adds back the old_column removed by cleanup_concurrent_column_rename. It also adds back the (old_column > new_column) trigger that is removed by cleanup_concurrent_column_rename.

table - The name of the database table containing the column. old - The old column name. new - The new column name. type - The type of the old column. If no type is given the new column’s

type is used.

batch_column_name - option is for tables without primary key, in this

case another unique integer column can be used. Example: :user_id



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# File 'lib/gitlab/database/migration_helpers.rb', line 582

def undo_cleanup_concurrent_column_rename(table, old, new, type: nil, batch_column_name: :id)
  unless column_exists?(table, batch_column_name)
    raise "Column #{batch_column_name} does not exist on #{table}"
  end

  if transaction_open?
    raise 'undo_cleanup_concurrent_column_rename can not be run inside a transaction'
  end

  check_trigger_permissions!(table)

  create_column_from(table, new, old, type: type, batch_column_name: batch_column_name)

  install_rename_triggers(table, old, new)
end

#undo_cleanup_concurrent_column_type_change(table, column, old_type, type_cast_function: nil, batch_column_name: :id, limit: nil, temp_column: nil) ⇒ Object

Reverses operations performed by cleanup_concurrent_column_type_change.

table - The table containing the column. column - The name of the column to change. old_type - The type of the original column used with change_column_type_concurrently. type_cast_function - Required if the conversion back to the original type is not automatic batch_column_name - option for tables without a primary key, in this case

another unique integer column can be used. Example: :user_id



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# File 'lib/gitlab/database/migration_helpers.rb', line 496

def undo_cleanup_concurrent_column_type_change(table, column, old_type, type_cast_function: nil, batch_column_name: :id, limit: nil, temp_column: nil)
  Gitlab::Database::QueryAnalyzers::RestrictAllowedSchemas.require_ddl_mode!

  temp_column ||= "#{column}_for_type_change"

  # Using a descriptive name that includes orinal column's name risks
  # taking us above the 63 character limit, so we use a hash
  identifier = "#{table}_#{column}_for_type_change"
  hashed_identifier = Digest::SHA256.hexdigest(identifier).first(10)
  temp_undo_cleanup_column = "tmp_undo_cleanup_column_#{hashed_identifier}"

  unless column_exists?(table, batch_column_name)
    raise "Column #{batch_column_name} does not exist on #{table}"
  end

  if transaction_open?
    raise 'undo_cleanup_concurrent_column_type_change can not be run inside a transaction'
  end

  check_trigger_permissions!(table)

  begin
    create_column_from(
      table,
      column,
      temp_undo_cleanup_column,
      type: old_type,
      batch_column_name: batch_column_name,
      type_cast_function: type_cast_function,
      limit: limit
    )

    transaction do
      # This has to be performed in a transaction as otherwise we might
      # have inconsistent data.
      rename_column(table, column, temp_column)
      rename_column(table, temp_undo_cleanup_column, column)

      install_rename_triggers(table, column, temp_column)
    end
  rescue StandardError
    # create_column_from can not run inside a transaction, which means
    #  that there is a risk that if any of the operations that follow it
    #  fail, we'll be left with an inconsistent schema
    # For those reasons, we make sure that we drop temp_undo_cleanup_column
    #  if an error is caught
    if column_exists?(table, temp_undo_cleanup_column)
      remove_column(table, temp_undo_cleanup_column)
    end

    raise
  end
end

#undo_rename_column_concurrently(table, old, new) ⇒ Object

Reverses operations performed by rename_column_concurrently.

This method takes care of removing previously installed triggers as well as removing the new column.

table - The name of the database table. old - The name of the old column. new - The name of the new column.



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# File 'lib/gitlab/database/migration_helpers.rb', line 398

def undo_rename_column_concurrently(table, old, new)
  trigger_name = rename_trigger_name(table, old, new)

  check_trigger_permissions!(table)

  remove_rename_triggers(table, trigger_name)

  remove_column(table, new)
end

#update_column_in_batches(table_name, column, value, batch_size: nil, batch_column_name: :id, disable_lock_writes: false) ⇒ Object

Updates the value of a column in batches.

This method updates the table in batches of 5% of the total row count. A ‘batch_size` option can also be passed to set this to a fixed number. This method will continue updating rows until no rows remain.

When given a block this method will yield two values to the block:

  1. An instance of ‘Arel::Table` for the table that is being updated.

  2. The query to run as an Arel object.

By supplying a block one can add extra conditions to the queries being executed. Note that the same block is used for all queries.

Example:

update_column_in_batches(:projects, :foo, 10) do |table, query|
  query.where(table[:some_column].eq('hello'))
end

This would result in this method updating only rows where ‘projects.some_column` equals “hello”.

table - The name of the table. column - The name of the column to update. value - The value for the column.

The ‘value` argument is typically a literal. To perform a computed update, an Arel literal can be used instead:

update_value = Arel.sql('bar * baz')

update_column_in_batches(:projects, :foo, update_value) do |table, query|
  query.where(table[:some_column].eq('hello'))
end

Rubocop’s Metrics/AbcSize metric is disabled for this method as Rubocop determines this method to be too complex while there’s no way to make it less “complex” without introducing extra methods (which actually will make things more complex).

‘batch_column_name` option is for tables without primary key, in this case another unique integer column can be used. Example: :user_id

rubocop: disable Metrics/AbcSize



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# File 'lib/gitlab/database/migration_helpers.rb', line 295

def update_column_in_batches(table_name, column, value, batch_size: nil, batch_column_name: :id, disable_lock_writes: false)
  if transaction_open?
    raise 'update_column_in_batches can not be run inside a transaction, ' \
      'you can disable transactions by calling disable_ddl_transaction! ' \
      'in the body of your migration class'
  end

  table = Arel::Table.new(table_name)

  count_arel = table.project(Arel.star.count.as('count'))
  count_arel = yield table, count_arel if block_given?

  total = exec_query(count_arel.to_sql).to_a.first['count'].to_i

  return if total == 0

  if batch_size.nil?
    # Update in batches of 5% until we run out of any rows to update.
    batch_size = ((total / 100.0) * 5.0).ceil
    max_size = 1000

    # The upper limit is 1000 to ensure we don't lock too many rows. For
    # example, for "merge_requests" even 1% of the table is around 35 000
    # rows for GitLab.com.
    batch_size = max_size if batch_size > max_size
  end

  start_arel = table.project(table[batch_column_name]).order(table[batch_column_name].asc).take(1)
  start_arel = yield table, start_arel if block_given?
  start_id = exec_query(start_arel.to_sql).to_a.first[batch_column_name.to_s].to_i

  loop do
    stop_arel = table.project(table[batch_column_name])
      .where(table[batch_column_name].gteq(start_id))
      .order(table[batch_column_name].asc)
      .take(1)
      .skip(batch_size)

    stop_arel = yield table, stop_arel if block_given?
    stop_row = exec_query(stop_arel.to_sql).to_a.first

    update_arel = Arel::UpdateManager.new
      .table(table)
      .set([[table[column], value]])
      .where(table[batch_column_name].gteq(start_id))

    if stop_row
      stop_id = stop_row[batch_column_name.to_s].to_i
      start_id = stop_id
      update_arel = update_arel.where(table[batch_column_name].lt(stop_id))
    end

    update_arel = yield table, update_arel if block_given?

    transaction do
      execute("SELECT set_config('lock_writes.#{table_name}', 'false', true)") if disable_lock_writes
      execute(update_arel.to_sql)
    end

    # There are no more rows left to update.
    break unless stop_row
  end
end