Class: ActiveRecord::ConnectionAdapters::AbstractMysqlAdapter

Inherits:
AbstractAdapter
  • Object
show all
Includes:
MySQL::Quoting, MySQL::SchemaStatements
Defined in:
lib/active_record/connection_adapters/abstract_mysql_adapter.rb

Direct Known Subclasses

Mysql2Adapter

Defined Under Namespace

Classes: MysqlString, StatementPool

Constant Summary collapse

NATIVE_DATABASE_TYPES = 
{
  primary_key: "bigint auto_increment PRIMARY KEY",
  string:      { name: "varchar", limit: 255 },
  text:        { name: "text" },
  integer:     { name: "int", limit: 4 },
  float:       { name: "float", limit: 24 },
  decimal:     { name: "decimal" },
  datetime:    { name: "datetime" },
  timestamp:   { name: "timestamp" },
  time:        { name: "time" },
  date:        { name: "date" },
  binary:      { name: "blob" },
  blob:        { name: "blob" },
  boolean:     { name: "tinyint", limit: 1 },
  json:        { name: "json" },
}

Constants inherited from AbstractAdapter

ActiveRecord::ConnectionAdapters::AbstractAdapter::ADAPTER_NAME, ActiveRecord::ConnectionAdapters::AbstractAdapter::SIMPLE_INT

Instance Attribute Summary

Attributes inherited from AbstractAdapter

#lock, #logger, #owner, #pool, #visitor

Attributes included from QueryCache

#query_cache, #query_cache_enabled

Attributes included from DatabaseStatements

#transaction_manager

Instance Method Summary collapse

Methods included from MySQL::SchemaStatements

#create_schema_dumper, #create_table, #indexes, #internal_string_options_for_primary_key, #remove_column, #table_alias_length, #type_to_sql, #update_table_definition

Methods included from MySQL::Quoting

#column_name_matcher, #column_name_with_order_matcher, #quote_column_name, #quote_table_name, #quoted_binary, #quoted_date, #unquoted_false, #unquoted_true

Methods inherited from AbstractAdapter

#active?, #adapter_name, #advisory_locks_enabled?, build_read_query_regexp, #case_insensitive_comparison, #close, #column_name_for_operation, database_exists?, #database_version, #disable_extension, #discard!, #disconnect!, #enable_extension, #expire, #extensions, #lease, #migration_context, #migrations_paths, #prefetch_primary_key?, #prepared_statements, #preventing_writes?, quoted_column_names, quoted_table_names, #raw_connection, #reconnect!, #replica?, #requires_reloading?, #reset!, #schema_cache, #schema_cache=, #schema_migration, #seconds_idle, #steal!, #supports_comments?, #supports_comments_in_create?, #supports_ddl_transactions?, #supports_extensions?, #supports_foreign_keys_in_create?, #supports_foreign_tables?, #supports_insert_conflict_target?, #supports_insert_returning?, #supports_json?, #supports_lazy_transactions?, #supports_materialized_views?, #supports_multi_insert?, #supports_partial_index?, #supports_savepoints?, #supports_validate_constraints?, type_cast_config_to_boolean, type_cast_config_to_integer, #unprepared_statement, #valid_type?, #verify!

Methods included from Savepoints

#create_savepoint, #current_savepoint_name, #exec_rollback_to_savepoint, #release_savepoint

Methods included from QueryCache

#cache, #clear_query_cache, dirties_query_cache, #disable_query_cache!, #enable_query_cache!, included, #select_all, #uncached

Methods included from DatabaseLimits

#allowed_index_name_length, #column_name_length, #columns_per_multicolumn_index, #columns_per_table, #in_clause_length, #index_name_length, #indexes_per_table, #joins_per_query, #max_identifier_length, #sql_query_length, #table_alias_length, #table_name_length

Methods included from Quoting

#column_name_matcher, #column_name_with_order_matcher, #lookup_cast_type_from_column, #quote, #quote_column_name, #quote_default_expression, #quote_string, #quote_table_name, #quote_table_name_for_assignment, #quoted_binary, #quoted_date, #quoted_false, #quoted_time, #quoted_true, #sanitize_as_sql_comment, #type_cast, #type_cast_from_column, #unquoted_false, #unquoted_true

Methods included from DatabaseStatements

#add_transaction_record, #cacheable_query, #default_sequence_name, #delete, #exec_delete, #exec_insert, #exec_query, #exec_update, #insert, #insert_fixture, #insert_fixtures_set, #query, #query_value, #query_values, #reset_sequence!, #reset_transaction, #rollback_db_transaction, #rollback_to_savepoint, #sanitize_limit, #select_all, #select_one, #select_rows, #select_value, #select_values, #to_sql, #transaction, #transaction_isolation_levels, #transaction_open?, #transaction_state, #truncate, #truncate_tables, #update, #with_yaml_fallback, #write_query?

Methods included from SchemaStatements

#add_column, #add_foreign_key, #add_index_options, #add_reference, #add_timestamps, #assume_migrated_upto_version, #change_table, #column_exists?, #columns, #create_join_table, #create_schema_dumper, #create_table, #data_source_exists?, #data_sources, #drop_join_table, #dump_schema_information, #foreign_key_column_for, #foreign_key_exists?, #foreign_key_options, #index_exists?, #index_name, #index_name_exists?, #indexes, #internal_string_options_for_primary_key, #options_include_default?, #primary_key, #remove_column, #remove_columns, #remove_foreign_key, #remove_index, #remove_reference, #remove_timestamps, #table_alias_for, #table_exists?, #tables, #type_to_sql, #update_table_definition, #view_exists?, #views

Constructor Details

#initialize(connection, logger, connection_options, config) ⇒ AbstractMysqlAdapter

Returns a new instance of AbstractMysqlAdapter.



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 54

def initialize(connection, logger, connection_options, config)
  super(connection, logger, config)
end

Instance Method Details

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

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 361

def add_index(table_name, column_name, options = {}) #:nodoc:
  index_name, index_type, index_columns, _, index_algorithm, index_using, comment = add_index_options(table_name, column_name, options)
  sql = +"CREATE #{index_type} INDEX #{quote_column_name(index_name)} #{index_using} ON #{quote_table_name(table_name)} (#{index_columns}) #{index_algorithm}"
  execute add_sql_comment!(sql, comment)
end

#add_sql_comment!(sql, comment) ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 367

def add_sql_comment!(sql, comment) # :nodoc:
  sql << " COMMENT #{quote(comment)}" if comment.present?
  sql
end

#begin_db_transaction ⇒ Object 



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 206

def begin_db_transaction
  execute "BEGIN"
end

#begin_isolated_db_transaction(isolation) ⇒ Object 



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 210

def begin_isolated_db_transaction(isolation)
  execute "SET TRANSACTION ISOLATION LEVEL #{transaction_isolation_levels.fetch(isolation)}"
  begin_db_transaction
end

#build_insert_sql(insert) ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 504

def build_insert_sql(insert) # :nodoc:
  sql = +"INSERT #{insert.into} #{insert.values_list}"

  if insert.skip_duplicates?
    no_op_column = quote_column_name(insert.keys.first)
    sql << " ON DUPLICATE KEY UPDATE #{no_op_column}=#{no_op_column}"
  elsif insert.update_duplicates?
    sql << " ON DUPLICATE KEY UPDATE "
    sql << insert.updatable_columns.map { |column| "#{column}=VALUES(#{column})" }.join(",")
  end

  sql
end

#case_sensitive_comparison(attribute, value) ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 466

def case_sensitive_comparison(attribute, value) # :nodoc:
  column = column_for_attribute(attribute)

  if column.collation && !column.case_sensitive?
    attribute.eq(Arel::Nodes::Bin.new(value))
  else
    super
  end
end

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

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 352

def change_column(table_name, column_name, type, options = {}) #:nodoc:
  execute("ALTER TABLE #{quote_table_name(table_name)} #{change_column_for_alter(table_name, column_name, type, options)}")
end

#change_column_comment(table_name, column_name, comment_or_changes) ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 347

def change_column_comment(table_name, column_name, comment_or_changes) # :nodoc:
  comment = extract_new_comment_value(comment_or_changes)
  change_column table_name, column_name, nil, comment: comment
end

#change_column_default(table_name, column_name, default_or_changes) ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 334

def change_column_default(table_name, column_name, default_or_changes) #:nodoc:
  default = extract_new_default_value(default_or_changes)
  change_column table_name, column_name, nil, default: default
end

#change_column_null(table_name, column_name, null, default = nil) ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 339

def change_column_null(table_name, column_name, null, default = nil) #:nodoc:
  unless null || default.nil?
    execute("UPDATE #{quote_table_name(table_name)} SET #{quote_column_name(column_name)}=#{quote(default)} WHERE #{quote_column_name(column_name)} IS NULL")
  end

  change_column table_name, column_name, nil, null: null
end

#change_table_comment(table_name, comment_or_changes) ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 290

def change_table_comment(table_name, comment_or_changes) # :nodoc:
  comment = extract_new_comment_value(comment_or_changes)
  comment = "" if comment.nil?
  execute("ALTER TABLE #{quote_table_name(table_name)} COMMENT #{quote(comment)}")
end

#charset ⇒ Object

Returns the database character set.



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 270

def charset
  show_variable "character_set_database"
end

#check_version ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 518

def check_version # :nodoc:
  if database_version < "5.5.8"
    raise "Your version of MySQL (#{database_version}) is too old. Active Record supports MySQL >= 5.5.8."
  end
end

#clear_cache! ⇒ Object

CONNECTION MANAGEMENT ====================================



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 170

def clear_cache! # :nodoc:
  reload_type_map
  super
end

#collation ⇒ Object

Returns the database collation strategy.



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 275

def collation
  show_variable "collation_database"
end

#columns_for_distinct(columns, orders) ⇒ Object

In MySQL 5.7.5 and up, ONLY_FULL_GROUP_BY affects handling of queries that use DISTINCT and ORDER BY. It requires the ORDER BY columns in the select list for distinct queries, and requires that the ORDER BY include the distinct column. See dev.mysql.com/doc/refman/5.7/en/group-by-handling.html



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 485

def columns_for_distinct(columns, orders) # :nodoc:
  order_columns = orders.reject(&:blank?).map { |s|
    # Convert Arel node to string
    s = s.to_sql unless s.is_a?(String)
    # Remove any ASC/DESC modifiers
    s.gsub(/\s+(?:ASC|DESC)\b/i, "")
  }.reject(&:blank?).map.with_index { |column, i| "#{column} AS alias_#{i}" }

  (order_columns << super).join(", ")
end

#commit_db_transaction ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 215

def commit_db_transaction #:nodoc:
  execute "COMMIT"
end

#create_database(name, options = {}) ⇒ Object

Create a new MySQL database with optional :charset and :collation. Charset defaults to utf8mb4.

Example:

create_database 'charset_test', charset: 'latin1', collation: 'latin1_bin'
create_database 'matt_development'
create_database 'matt_development', charset: :big5



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 245

def create_database(name, options = {})
  if options[:collation]
    execute "CREATE DATABASE #{quote_table_name(name)} DEFAULT COLLATE #{quote_table_name(options[:collation])}"
  elsif options[:charset]
    execute "CREATE DATABASE #{quote_table_name(name)} DEFAULT CHARACTER SET #{quote_table_name(options[:charset])}"
  elsif row_format_dynamic_by_default?
    execute "CREATE DATABASE #{quote_table_name(name)} DEFAULT CHARACTER SET `utf8mb4`"
  else
    raise "Configure a supported :charset and ensure innodb_large_prefix is enabled to support indexes on varchar(255) string columns."
  end
end

#current_database ⇒ Object 



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 265

def current_database
  query_value("SELECT database()", "SCHEMA")
end

#default_index_type?(index) ⇒ Boolean

:nodoc:

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 500

def default_index_type?(index) # :nodoc:
  index.using == :btree || super
end

#default_uniqueness_comparison(attribute, value, klass) ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 451

def default_uniqueness_comparison(attribute, value, klass) # :nodoc:
  column = column_for_attribute(attribute)

  if column.collation && !column.case_sensitive? && !value.nil?
    ActiveSupport::Deprecation.warn(<<~MSG.squish)
      Uniqueness validator will no longer enforce case sensitive comparison in Rails 6.1.
      To continue case sensitive comparison on the :#{attribute.name} attribute in #{klass} model,
      pass `case_sensitive: true` option explicitly to the uniqueness validator.
    MSG
    attribute.eq(Arel::Nodes::Bin.new(value))
  else
    super
  end
end

#disable_referential_integrity ⇒ Object

REFERENTIAL INTEGRITY ====================================



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 157

def disable_referential_integrity #:nodoc:
  old = query_value("SELECT @@FOREIGN_KEY_CHECKS")

  begin
    update("SET FOREIGN_KEY_CHECKS = 0")
    yield
  ensure
    update("SET FOREIGN_KEY_CHECKS = #{old}")
  end
end

#drop_database(name) ⇒ Object

Drops a MySQL database.

Example:

drop_database('sebastian_development')



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 261

def drop_database(name) #:nodoc:
  execute "DROP DATABASE IF EXISTS #{quote_table_name(name)}"
end

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

Drops a table from the database.

:force

Set to :cascade to drop dependent objects as well. Defaults to false.

:if_exists

Set to true to only drop the table if it exists. Defaults to false.

:temporary

Set to true to drop temporary table. Defaults to false.

Although this command ignores most options and the block if one is given, it can be helpful to provide these in a migration’s change method so it can be reverted. In that case, options and the block will be used by create_table.



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 320

def drop_table(table_name, options = {})
  execute "DROP#{' TEMPORARY' if options[:temporary]} TABLE#{' IF EXISTS' if options[:if_exists]} #{quote_table_name(table_name)}#{' CASCADE' if options[:force] == :cascade}"
end

#each_hash(result) ⇒ Object

The two drivers have slightly different ways of yielding hashes of results, so this method must be implemented to provide a uniform interface.

Raises:

  • (NotImplementedError) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 145

def each_hash(result) # :nodoc:
  raise NotImplementedError
end

#empty_insert_statement_value(primary_key = nil) ⇒ Object 



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 223

def empty_insert_statement_value(primary_key = nil)
  "VALUES ()"
end

#emulate_booleans ⇒ Object

:singleton-method: By default, the Mysql2Adapter will consider all columns of type tinyint(1) as boolean. If you wish to disable this emulation you can add the following line to your application.rb file:

ActiveRecord::ConnectionAdapters::Mysql2Adapter.emulate_booleans = false



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 27

class_attribute :emulate_booleans, default: true

#error_number(exception) ⇒ Object

Must return the MySQL error number from the exception, if the exception has an error number.

Raises:

  • (NotImplementedError) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 151

def error_number(exception) # :nodoc:
  raise NotImplementedError
end

#exec_rollback_db_transaction ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 219

def exec_rollback_db_transaction #:nodoc:
  execute "ROLLBACK"
end

#execute(sql, name = nil) ⇒ Object

Executes the SQL statement in the context of this connection.



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 189

def execute(sql, name = nil)
  materialize_transactions

  log(sql, name) do
    ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
      @connection.query(sql)
    end
  end
end

#execute_and_free(sql, name = nil) {|execute(sql, name)| ... } ⇒ Object

Mysql2Adapter doesn’t have to free a result after using it, but we use this method to write stuff in an abstract way without concerning ourselves about whether it needs to be explicitly freed or not.

Yields:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 202

def execute_and_free(sql, name = nil) # :nodoc:
  yield execute(sql, name)
end

#explain(arel, binds = []) ⇒ Object

– DATABASE STATEMENTS ====================================== ++



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 179

def explain(arel, binds = [])
  sql     = "EXPLAIN #{to_sql(arel, binds)}"
  start   = Concurrent.monotonic_time
  result  = exec_query(sql, "EXPLAIN", binds)
  elapsed = Concurrent.monotonic_time - start

  MySQL::ExplainPrettyPrinter.new.pp(result, elapsed)
end

#foreign_keys(table_name) ⇒ Object

Raises:

  • (ArgumentError) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 372

def foreign_keys(table_name)
  raise ArgumentError unless table_name.present?

  scope = quoted_scope(table_name)

  fk_info = exec_query(<<~SQL, "SCHEMA")
    SELECT fk.referenced_table_name AS 'to_table',
           fk.referenced_column_name AS 'primary_key',
           fk.column_name AS 'column',
           fk.constraint_name AS 'name',
           rc.update_rule AS 'on_update',
           rc.delete_rule AS 'on_delete'
    FROM information_schema.referential_constraints rc
    JOIN information_schema.key_column_usage fk
    USING (constraint_schema, constraint_name)
    WHERE fk.referenced_column_name IS NOT NULL
      AND fk.table_schema = #{scope[:schema]}
      AND fk.table_name = #{scope[:name]}
      AND rc.constraint_schema = #{scope[:schema]}
      AND rc.table_name = #{scope[:name]}
  SQL

  fk_info.map do |row|
    options = {
      column: row["column"],
      name: row["name"],
      primary_key: row["primary_key"]
    }

    options[:on_update] = extract_foreign_key_action(row["on_update"])
    options[:on_delete] = extract_foreign_key_action(row["on_delete"])

    ForeignKeyDefinition.new(table_name, row["to_table"], options)
  end
end

#get_advisory_lock(lock_name, timeout = 0) ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 125

def get_advisory_lock(lock_name, timeout = 0) # :nodoc:
  query_value("SELECT GET_LOCK(#{quote(lock_name.to_s)}, #{timeout})") == 1
end

#get_database_version ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 58

def get_database_version #:nodoc:
  full_version_string = get_full_version
  version_string = version_string(full_version_string)
  Version.new(version_string, full_version_string)
end

#index_algorithms ⇒ Object 



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 137

def index_algorithms
  { default: +"ALGORITHM = DEFAULT", copy: +"ALGORITHM = COPY", inplace: +"ALGORITHM = INPLACE" }
end

#mariadb? ⇒ Boolean

:nodoc:

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 64

def mariadb? # :nodoc:
  /mariadb/i.match?(full_version)
end

#native_database_types ⇒ Object 



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 133

def native_database_types
  NATIVE_DATABASE_TYPES
end

#primary_keys(table_name) ⇒ Object

:nodoc:

Raises:

  • (ArgumentError) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 436

def primary_keys(table_name) # :nodoc:
  raise ArgumentError unless table_name.present?

  scope = quoted_scope(table_name)

  query_values(<<~SQL, "SCHEMA")
    SELECT column_name
    FROM information_schema.key_column_usage
    WHERE constraint_name = 'PRIMARY'
      AND table_schema = #{scope[:schema]}
      AND table_name = #{scope[:name]}
    ORDER BY ordinal_position
  SQL
end

#recreate_database(name, options = {}) ⇒ Object

Drops the database specified on the name attribute and creates it again using the provided options.



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 231

def recreate_database(name, options = {})
  drop_database(name)
  sql = create_database(name, options)
  reconnect!
  sql
end

#release_advisory_lock(lock_name) ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 129

def release_advisory_lock(lock_name) # :nodoc:
  query_value("SELECT RELEASE_LOCK(#{quote(lock_name.to_s)})") == 1
end

#rename_column(table_name, column_name, new_column_name) ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 356

def rename_column(table_name, column_name, new_column_name) #:nodoc:
  execute("ALTER TABLE #{quote_table_name(table_name)} #{rename_column_for_alter(table_name, column_name, new_column_name)}")
  rename_column_indexes(table_name, column_name, new_column_name)
end

#rename_index(table_name, old_name, new_name) ⇒ Object 



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 324

def rename_index(table_name, old_name, new_name)
  if supports_rename_index?
    validate_index_length!(table_name, new_name)

    execute "ALTER TABLE #{quote_table_name(table_name)} RENAME INDEX #{quote_table_name(old_name)} TO #{quote_table_name(new_name)}"
  else
    super
  end
end

#rename_table(table_name, new_name) ⇒ Object

Renames a table.

Example:

rename_table('octopuses', 'octopi')



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 300

def rename_table(table_name, new_name)
  execute "RENAME TABLE #{quote_table_name(table_name)} TO #{quote_table_name(new_name)}"
  rename_table_indexes(table_name, new_name)
end

#show_variable(name) ⇒ Object

SHOW VARIABLES LIKE ‘name’



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 430

def show_variable(name)
  query_value("SELECT @@#{name}", "SCHEMA")
rescue ActiveRecord::StatementInvalid
  nil
end

#strict_mode? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 496

def strict_mode?
  self.class.type_cast_config_to_boolean(@config.fetch(:strict, true))
end

#supports_advisory_locks? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 113

def supports_advisory_locks?
  true
end

#supports_bulk_alter? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 68

def supports_bulk_alter?
  true
end

#supports_datetime_with_precision? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 100

def supports_datetime_with_precision?
  mariadb? || database_version >= "5.6.4"
end

#supports_explain? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 84

def supports_explain?
  true
end

#supports_expression_index? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 76

def supports_expression_index?
  !mariadb? && database_version >= "8.0.13"
end

#supports_foreign_keys? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 92

def supports_foreign_keys?
  true
end

#supports_index_sort_order? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 72

def supports_index_sort_order?
  !mariadb? && database_version >= "8.0.1"
end

#supports_indexes_in_create? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 88

def supports_indexes_in_create?
  true
end

#supports_insert_on_duplicate_skip? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 117

def supports_insert_on_duplicate_skip?
  true
end

#supports_insert_on_duplicate_update? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 121

def supports_insert_on_duplicate_update?
  true
end

#supports_optimizer_hints? ⇒ Boolean

See dev.mysql.com/doc/refman/8.0/en/optimizer-hints.html for more details.

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 109

def supports_optimizer_hints?
  !mariadb? && database_version >= "5.7.7"
end

#supports_transaction_isolation? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 80

def supports_transaction_isolation?
  true
end

#supports_views? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 96

def supports_views?
  true
end

#supports_virtual_columns? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 104

def supports_virtual_columns?
  mariadb? || database_version >= "5.7.5"
end

#table_comment(table_name) ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 279

def table_comment(table_name) # :nodoc:
  scope = quoted_scope(table_name)

  query_value(<<~SQL, "SCHEMA").presence
    SELECT table_comment
    FROM information_schema.tables
    WHERE table_schema = #{scope[:schema]}
      AND table_name = #{scope[:name]}
  SQL
end

#table_options(table_name) ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 408

def table_options(table_name) # :nodoc:
  table_options = {}

  create_table_info = create_table_info(table_name)

  # strip create_definitions and partition_options
  raw_table_options = create_table_info.sub(/\A.*\n\) /m, "").sub(/\n\/\*!.*\*\/\n\z/m, "").strip

  # strip AUTO_INCREMENT
  raw_table_options.sub!(/(ENGINE=\w+)(?: AUTO_INCREMENT=\d+)/, '\1')

  table_options[:options] = raw_table_options

  # strip COMMENT
  if raw_table_options.sub!(/ COMMENT='.+'/, "")
    table_options[:comment] = table_comment(table_name)
  end

  table_options
end