Module: Sequel::SQLite::DatabaseMethods

Included in:
Amalgalite::Database, DataObjects::SQLite::DatabaseMethods, JDBC::SQLite::DatabaseMethods, Database, Sequel::Swift::SQLite::DatabaseMethods
Defined in:
lib/sequel/adapters/shared/sqlite.rb

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 collapse

AUTO_VACUUM = 
[:none, :full, :incremental].freeze
PRIMARY_KEY_INDEX_RE = 
/\Asqlite_autoindex_/.freeze
SYNCHRONOUS = 
[:off, :normal, :full].freeze
TABLES_FILTER = 
"type = 'table' AND NOT name = 'sqlite_sequence'".freeze
TEMP_STORE = 
[:default, :file, :memory].freeze
VIEWS_FILTER = 
"type = 'view'".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

Instance Attribute Details

#integer_booleans ⇒ Object

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 22

def integer_booleans
  @integer_booleans
end

#use_timestamp_timezones=(value) ⇒ Object (writeonly)

Override the default setting for whether to use timezones in timestamps. For backwards compatibility, it is set to true by default. Anyone wanting to use SQLite’s datetime functions should set it to false using this method. It’s possible that the default will change in a future version, so anyone relying on timezones in timestamps should set this to true.



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# File 'lib/sequel/adapters/shared/sqlite.rb', line 158

def use_timestamp_timezones=(value)
  @use_timestamp_timezones = value
end

Instance Method Details

#auto_vacuum ⇒ Object

A symbol signifying the value of the auto_vacuum PRAGMA.



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# File 'lib/sequel/adapters/shared/sqlite.rb', line 25

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 32

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 40

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

#database_type ⇒ Object

SQLite uses the :sqlite database type.



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# File 'lib/sequel/adapters/shared/sqlite.rb', line 58

def database_type
  :sqlite
end

#foreign_key_list(table, 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 77

def foreign_key_list(table, opts={})
  m = output_identifier_meth
  h = {}
  metadata_dataset.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_keys ⇒ Object

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 64

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 71

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

#indexes(table, 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 92

def indexes(table, opts={})
  m = output_identifier_meth
  im = input_identifier_meth
  indexes = {}
  metadata_dataset.with_sql("PRAGMA index_list(?)", im.call(table)).each do |r|
    next if r[:name] =~ PRIMARY_KEY_INDEX_RE
    indexes[m.call(r[:name])] = {:unique=>r[:unique].to_i==1}
  end
  indexes.each do |k, v|
    v[:columns] = metadata_dataset.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 107

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 117

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

#set_integer_booleans ⇒ Object

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



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# File 'lib/sequel/adapters/shared/sqlite.rb', line 122

def set_integer_booleans
  @integer_booleans = typecast_value_boolean(@opts[:integer_booleans])
end

#sqlite_version ⇒ Object

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 128

def sqlite_version
  return @sqlite_version if defined?(@sqlite_version)
  @sqlite_version = begin
    v = get{sqlite_version{}}
    [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 139

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 144

def supports_deferrable_foreign_key_constraints?
  sqlite_version >= 30619
end

#supports_savepoints? ⇒ Boolean

SQLite 3.6.8+ supports savepoints.

Returns:

  • (Boolean) 


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# File 'lib/sequel/adapters/shared/sqlite.rb', line 149

def supports_savepoints?
  sqlite_version >= 30608
end

#synchronous ⇒ Object

A symbol signifying the value of the synchronous PRAGMA.



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

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 173

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 = {}) ⇒ 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 182

def tables(opts={})
  tables_and_views(TABLES_FILTER, opts)
end

#temp_store ⇒ Object

A symbol signifying the value of the temp_store PRAGMA.



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# File 'lib/sequel/adapters/shared/sqlite.rb', line 187

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 193

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

#transaction_mode ⇒ Object

A symbol signifying the value of the default transaction mode



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# File 'lib/sequel/adapters/shared/sqlite.rb', line 45

def transaction_mode
  defined?(@transaction_mode) ? @transaction_mode : (@transaction_mode = nil)
end

#transaction_mode=(value) ⇒ Object 



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# File 'lib/sequel/adapters/shared/sqlite.rb', line 49

def transaction_mode=(value)
  if TRANSACTION_MODE.include?(value)
    @transaction_mode = value
  else
    raise Error, "Invalid value for transaction_mode.  Please specify one of :deferred, :immediate, :exclusive, nil"
  end
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 162

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

#views(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 202

def views(opts={})
  tables_and_views(VIEWS_FILTER, opts)
end