Module: Sequel::SQLite::DatabaseMethods

Overview

No matter how you connect to SQLite, the following Database options can be used to set PRAGMAs on connections in a thread-safe manner: :auto_vacuum, :foreign_keys, :synchronous, and :temp_store.

Constant Summary

AUTO_VACUUM =
[:none, :full, :incremental].freeze
PRIMARY_KEY_INDEX_RE =
/\Asqlite_autoindex_/.freeze
SYNCHRONOUS =
[:off, :normal, :full].freeze
TABLES_FILTER =
Sequel.~(:name=>'sqlite_sequence'.freeze) & {:type => 'table'.freeze}
TEMP_STORE =
[:default, :file, :memory].freeze
VIEWS_FILTER =
{:type => 'view'.freeze}.freeze
TRANSACTION_MODE =
{
  :deferred => "BEGIN DEFERRED TRANSACTION".freeze,
  :immediate => "BEGIN IMMEDIATE TRANSACTION".freeze,
  :exclusive => "BEGIN EXCLUSIVE TRANSACTION".freeze,
  nil => Sequel::Database::SQL_BEGIN,
}.freeze

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from Database::ResetIdentifierMangling

extended

Instance Attribute Details

#integer_booleansObject

Whether to use integers for booleans in the database. SQLite recommends booleans be stored as integers, but historically Sequel has used 't'/'f'.



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# File 'lib/sequel/adapters/shared/sqlite.rb', line 28

def integer_booleans
  @integer_booleans
end

#transaction_modeObject

A symbol signifying the value of the default transaction mode



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# File 'lib/sequel/adapters/shared/sqlite.rb', line 51

def transaction_mode
  @transaction_mode
end

#use_timestamp_timezones=(value) ⇒ Object (writeonly)

Override the default setting for whether to use timezones in timestamps. It is set to false by default, as SQLite's date/time methods do not support timezones in timestamps.



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# File 'lib/sequel/adapters/shared/sqlite.rb', line 167

def use_timestamp_timezones=(value)
  @use_timestamp_timezones = value
end

Instance Method Details

#auto_vacuumObject

A symbol signifying the value of the auto_vacuum PRAGMA.



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# File 'lib/sequel/adapters/shared/sqlite.rb', line 31

def auto_vacuum
  AUTO_VACUUM[pragma_get(:auto_vacuum).to_i]
end

#auto_vacuum=(value) ⇒ Object

Set the auto_vacuum PRAGMA using the given symbol (:none, :full, or :incremental). See pragma_set. Consider using the :auto_vacuum Database option instead.



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# File 'lib/sequel/adapters/shared/sqlite.rb', line 38

def auto_vacuum=(value)
  value = AUTO_VACUUM.index(value) || (raise Error, "Invalid value for auto_vacuum option. Please specify one of :none, :full, :incremental.")
  pragma_set(:auto_vacuum, value)
end

#case_sensitive_like=(value) ⇒ Object

Set the case_sensitive_like PRAGMA using the given boolean value, if using SQLite 3.2.3+. If not using 3.2.3+, no error is raised. See pragma_set. Consider using the :case_sensitive_like Database option instead.



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# File 'lib/sequel/adapters/shared/sqlite.rb', line 46

def case_sensitive_like=(value)
  pragma_set(:case_sensitive_like, !!value ? 'on' : 'off') if sqlite_version >= 30203
end

#database_typeObject

SQLite uses the :sqlite database type.



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# File 'lib/sequel/adapters/shared/sqlite.rb', line 63

def database_type
  :sqlite
end

#foreign_key_list(table, opts = OPTS) ⇒ Object

Return the array of foreign key info hashes using the foreign_key_list PRAGMA, including information for the :on_update and :on_delete entries.



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# File 'lib/sequel/adapters/shared/sqlite.rb', line 82

def foreign_key_list(table, opts=OPTS)
  m = output_identifier_meth
  h = {}
  .with_sql("PRAGMA foreign_key_list(?)", input_identifier_meth.call(table)).each do |row|
    if r = h[row[:id]]
      r[:columns] << m.call(row[:from])
      r[:key] << m.call(row[:to]) if r[:key]
    else
      h[row[:id]] = {:columns=>[m.call(row[:from])], :table=>m.call(row[:table]), :key=>([m.call(row[:to])] if row[:to]), :on_update=>on_delete_sql_to_sym(row[:on_update]), :on_delete=>on_delete_sql_to_sym(row[:on_delete])}
    end
  end
  h.values
end

#foreign_keysObject

Boolean signifying the value of the foreign_keys PRAGMA, or nil if not using SQLite 3.6.19+.



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# File 'lib/sequel/adapters/shared/sqlite.rb', line 69

def foreign_keys
  pragma_get(:foreign_keys).to_i == 1 if sqlite_version >= 30619
end

#foreign_keys=(value) ⇒ Object

Set the foreign_keys PRAGMA using the given boolean value, if using SQLite 3.6.19+. If not using 3.6.19+, no error is raised. See pragma_set. Consider using the :foreign_keys Database option instead.



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# File 'lib/sequel/adapters/shared/sqlite.rb', line 76

def foreign_keys=(value)
  pragma_set(:foreign_keys, !!value ? 'on' : 'off') if sqlite_version >= 30619
end

#indexes(table, opts = OPTS) ⇒ Object

Use the index_list and index_info PRAGMAs to determine the indexes on the table.



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# File 'lib/sequel/adapters/shared/sqlite.rb', line 97

def indexes(table, opts=OPTS)
  m = output_identifier_meth
  im = input_identifier_meth
  indexes = {}
  .with_sql("PRAGMA index_list(?)", im.call(table)).each do |r|
    # :only_autocreated internal option can be used to get only autocreated indexes
    next if (!!(r[:name] =~ PRIMARY_KEY_INDEX_RE) ^ !!opts[:only_autocreated])
    indexes[m.call(r[:name])] = {:unique=>r[:unique].to_i==1}
  end
  indexes.each do |k, v|
    v[:columns] = .with_sql("PRAGMA index_info(?)", im.call(k)).map(:name).map{|x| m.call(x)}
  end
  indexes
end

#pragma_get(name) ⇒ Object

Get the value of the given PRAGMA.



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# File 'lib/sequel/adapters/shared/sqlite.rb', line 113

def pragma_get(name)
  self["PRAGMA #{name}"].single_value
end

#pragma_set(name, value) ⇒ Object

Set the value of the given PRAGMA to value.

This method is not thread safe, and will not work correctly if there are multiple connections in the Database's connection pool. PRAGMA modifications should be done when the connection is created, using an option provided when creating the Database object.



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# File 'lib/sequel/adapters/shared/sqlite.rb', line 123

def pragma_set(name, value)
  execute_ddl("PRAGMA #{name} = #{value}")
end

#set_integer_booleansObject

Set the integer_booleans option using the passed in :integer_boolean option.



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# File 'lib/sequel/adapters/shared/sqlite.rb', line 128

def set_integer_booleans
  @integer_booleans = @opts.has_key?(:integer_booleans) ? typecast_value_boolean(@opts[:integer_booleans]) : true
end

#sqlite_versionObject

The version of the server as an integer, where 3.6.19 = 30619. If the server version can't be determined, 0 is used.



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# File 'lib/sequel/adapters/shared/sqlite.rb', line 134

def sqlite_version
  return @sqlite_version if defined?(@sqlite_version)
  @sqlite_version = begin
    v = fetch('SELECT sqlite_version()').single_value
    [10000, 100, 1].zip(v.split('.')).inject(0){|a, m| a + m[0] * Integer(m[1])}
  rescue
    0
  end
end

#supports_create_table_if_not_exists?Boolean

SQLite supports CREATE TABLE IF NOT EXISTS syntax since 3.3.0.

Returns:

  • (Boolean)


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# File 'lib/sequel/adapters/shared/sqlite.rb', line 145

def supports_create_table_if_not_exists?
  sqlite_version >= 30300
end

#supports_deferrable_foreign_key_constraints?Boolean

SQLite 3.6.19+ supports deferrable foreign key constraints.

Returns:

  • (Boolean)


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# File 'lib/sequel/adapters/shared/sqlite.rb', line 150

def supports_deferrable_foreign_key_constraints?
  sqlite_version >= 30619
end

#supports_partial_indexes?Boolean

SQLite 3.8.0+ supports partial indexes.

Returns:

  • (Boolean)


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# File 'lib/sequel/adapters/shared/sqlite.rb', line 155

def supports_partial_indexes?
  sqlite_version >= 30800
end

#supports_savepoints?Boolean

SQLite 3.6.8+ supports savepoints.

Returns:

  • (Boolean)


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# File 'lib/sequel/adapters/shared/sqlite.rb', line 160

def supports_savepoints?
  sqlite_version >= 30608
end

#synchronousObject

A symbol signifying the value of the synchronous PRAGMA.



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# File 'lib/sequel/adapters/shared/sqlite.rb', line 176

def synchronous
  SYNCHRONOUS[pragma_get(:synchronous).to_i]
end

#synchronous=(value) ⇒ Object

Set the synchronous PRAGMA using the given symbol (:off, :normal, or :full). See pragma_set. Consider using the :synchronous Database option instead.



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# File 'lib/sequel/adapters/shared/sqlite.rb', line 182

def synchronous=(value)
  value = SYNCHRONOUS.index(value) || (raise Error, "Invalid value for synchronous option. Please specify one of :off, :normal, :full.")
  pragma_set(:synchronous, value)
end

#tables(opts = OPTS) ⇒ Object

Array of symbols specifying the table names in the current database.

Options:

:server

Set the server to use.



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# File 'lib/sequel/adapters/shared/sqlite.rb', line 191

def tables(opts=OPTS)
  tables_and_views(TABLES_FILTER, opts)
end

#temp_storeObject

A symbol signifying the value of the temp_store PRAGMA.



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# File 'lib/sequel/adapters/shared/sqlite.rb', line 196

def temp_store
  TEMP_STORE[pragma_get(:temp_store).to_i]
end

#temp_store=(value) ⇒ Object

Set the temp_store PRAGMA using the given symbol (:default, :file, or :memory). See pragma_set. Consider using the :temp_store Database option instead.



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# File 'lib/sequel/adapters/shared/sqlite.rb', line 202

def temp_store=(value)
  value = TEMP_STORE.index(value) || (raise Error, "Invalid value for temp_store option. Please specify one of :default, :file, :memory.")
  pragma_set(:temp_store, value)
end

#use_timestamp_timezones?Boolean

SQLite supports timezones in timestamps, since it just stores them as strings, but it breaks the usage of SQLite's datetime functions.

Returns:

  • (Boolean)


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# File 'lib/sequel/adapters/shared/sqlite.rb', line 171

def use_timestamp_timezones?
  defined?(@use_timestamp_timezones) ? @use_timestamp_timezones : (@use_timestamp_timezones = false)
end

#values(v) ⇒ Object

Creates a dataset that uses the VALUES clause:

DB.values([[1, 2], [3, 4]])
VALUES ((1, 2), (3, 4))


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# File 'lib/sequel/adapters/shared/sqlite.rb', line 211

def values(v)
  @default_dataset.clone(:values=>v)
end

#views(opts = OPTS) ⇒ Object

Array of symbols specifying the view names in the current database.

Options:

:server

Set the server to use.



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# File 'lib/sequel/adapters/shared/sqlite.rb', line 219

def views(opts=OPTS)
  tables_and_views(VIEWS_FILTER, opts)
end