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class ActiveRecord::ConnectionAdapters::SQLite3Adapter

Active Record SQLite3 Adapter

The SQLite3 adapter works with the sqlite3 driver.

Options:

  • :database (String): Filesystem path to the database file.

  • :statement_limit (Integer): Maximum number of prepared statements to cache per database connection. (default: 1000)

  • :timeout (Integer): Timeout in milliseconds to use when waiting for a lock. (default: no wait)

  • :strict (Boolean): Enable or disable strict mode. When enabled, this will disallow double-quoted string literals in SQL statements. (default: see strict_strings_by_default)

  • :extensions (Array): (requires sqlite3 v2.4.0) Each entry specifies a sqlite extension to load for this database. The entry may be a filesystem path, or the name of a class that responds to .to_path to provide the filesystem path for the extension. See sqlite3-ruby documentation for more information.

There may be other options available specific to the SQLite3 driver. Please read the documentation for SQLite::Database.new

Inherits From

Constants

ADAPTER_NAME

"SQLite"

COLLATE_REGEX

/.*"(\w+)".*collate\s+"(\w+)".*/i

DEFAULT_PRAGMAS

{
"foreign_keys"        => true,
"journal_mode"        => :wal,
"synchronous"         => :normal,
"mmap_size"           => 134217728, # 128 megabytes
"journal_size_limit"  => 67108864, # 64 megabytes
"cache_size"          => 2000
}

DEFERRABLE_REGEX

/DEFERRABLE INITIALLY (\w+)/

EXTENDED_TYPE_MAPS

Concurrent::Map.new

FINAL_CLOSE_PARENS_REGEX

/\);*\z/

FK_REGEX

/.*FOREIGN KEY\s+\("([^"]+)"\)\s+REFERENCES\s+"(\w+)"\s+\("(\w+)"\)/

GENERATED_ALWAYS_AS_REGEX

/.*"(\w+)".+GENERATED ALWAYS AS \((.+)\) (?:STORED|VIRTUAL)/i

NATIVE_DATABASE_TYPES

{
primary_key:  "integer PRIMARY KEY AUTOINCREMENT NOT NULL",
string:       { name: "varchar" },
text:         { name: "text" },
integer:      { name: "integer" },
float:        { name: "float" },
decimal:      { name: "decimal" },
datetime:     { name: "datetime" },
time:         { name: "time" },
date:         { name: "date" },
binary:       { name: "blob" },
boolean:      { name: "boolean" },
json:         { name: "json" },
}

PRIMARY_KEY_AUTOINCREMENT_REGEX

/.*"(\w+)".+PRIMARY KEY AUTOINCREMENT/i

TYPE_MAP

Type::TypeMap.new.tap { |m| initialize_type_map(m) }

UNQUOTED_OPEN_PARENS_REGEX

/\((?![^'"]*['"][^'"]*$)/

VIRTUAL_TABLE_REGEX

/USING\s+(\w+)\s*\((.+)\)/i

Public class methods

dbconsole(config, options = {})

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 60
def dbconsole(config, options = {})
  args = []

  args << "-#{options[:mode]}" if options[:mode]
  args << "-header" if options[:header]
  args << File.expand_path(config.database, defined?(Rails.root) ? Rails.root : nil)

  find_cmd_and_exec(ActiveRecord.database_cli[:sqlite], *args)
end

new(...)

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 129
def initialize(...)
  super

  @memory_database = false
  case @config[:database].to_s
  when ""
    raise ArgumentError, "No database file specified. Missing argument: database"
  when ":memory:"
    @memory_database = true
  when /\Afile:/
  else
    # Otherwise we have a path relative to Rails.root
    @config[:database] = File.expand_path(@config[:database], Rails.root) if defined?(Rails.root)
    dirname = File.dirname(@config[:database])
    unless File.directory?(dirname)
      begin
        FileUtils.mkdir_p(dirname)
      rescue SystemCallError
        raise ActiveRecord::NoDatabaseError.new(connection_pool: @pool)
      end
    end
  end

  @last_affected_rows = nil
  @previous_read_uncommitted = nil
  @config[:strict] = ConnectionAdapters::SQLite3Adapter.strict_strings_by_default unless @config.key?(:strict)

  extensions = @config.fetch(:extensions, []).map do |extension|
    extension.safe_constantize || extension
  end

  @connection_parameters = @config.merge(
    database: @config[:database].to_s,
    results_as_hash: true,
    default_transaction_mode: :immediate,
    extensions: extensions
  )
end

new_client(config)

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 50
def new_client(config)
  ::SQLite3::Database.new(config[:database].to_s, config)
rescue Errno::ENOENT => error
  if error.message.include?("No such file or directory")
    raise ActiveRecord::NoDatabaseError
  else
    raise
  end
end

strict_strings_by_default

Configure the SQLite3Adapter to be used in a “strict strings” mode. When enabled, this will disallow double-quoted string literals in SQL statements, which may prevent some typographical errors like creating an index for a non-existent column. The default is false.

If you wish to enable this mode you can add the following line to your application.rb file:

config.active_record.sqlite3_adapter_strict_strings_by_default = true

This can also be configured on individual databases by setting the strict: option.

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 94
class_attribute :strict_strings_by_default, default: false

Public instance methods

active?()

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 243
def active?
  if connected?
    verified!
    true
  end
end

add_timestamps(table_name, **options)

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 426
def add_timestamps(table_name, **options)
  options[:null] = false if options[:null].nil?

  if !options.key?(:precision)
    options[:precision] = 6
  end

  alter_table(table_name) do |definition|
    definition.column :created_at, :datetime, **options
    definition.column :updated_at, :datetime, **options
  end
end

connected?()

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 239
def connected?
  !(@raw_connection.nil? || @raw_connection.closed?)
end

create_virtual_table(table_name, module_name, values)

Creates a virtual table

Example:

create_virtual_table :emails, :fts5, ['sender', 'title',' body']
Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 342
def create_virtual_table(table_name, module_name, values)
  exec_query "CREATE VIRTUAL TABLE IF NOT EXISTS #{table_name} USING #{module_name} (#{values.join(", ")})"
end

database_exists?()

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 168
def database_exists?
  @config[:database] == ":memory:" || File.exist?(@config[:database].to_s)
end

disconnect!()

Disconnects from the database if already connected. Otherwise, this method does nothing.

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 254
def disconnect!
  super

  @raw_connection&.close rescue nil
  @raw_connection = nil
end

drop_virtual_table(table_name, module_name, values, **options)

Drops a virtual table

Although this command ignores module_name and values, it can be helpful to provide these in a migration’s change method so it can be reverted. In that case, module_name, values and options will be used by create_virtual_table.

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 351
def drop_virtual_table(table_name, module_name, values, **options)
  drop_table(table_name)
end

encoding()

Returns the current database encoding format as a string, e.g. ‘UTF-8’

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 266
def encoding
  any_raw_connection.encoding.to_s
end

foreign_keys(table_name)

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 446
def foreign_keys(table_name)
  # SQLite returns 1 row for each column of composite foreign keys.
  fk_info = internal_exec_query("PRAGMA foreign_key_list(#{quote(table_name)})", "SCHEMA")
  # Deferred or immediate foreign keys can only be seen in the CREATE TABLE sql
  fk_defs = table_structure_sql(table_name)
              .select do |column_string|
                column_string.start_with?("CONSTRAINT") &&
                column_string.include?("FOREIGN KEY")
              end
              .to_h do |fk_string|
                _, from, table, to = fk_string.match(FK_REGEX).to_a
                _, mode = fk_string.match(DEFERRABLE_REGEX).to_a
                deferred = mode&.downcase&.to_sym || false
                [[table, from, to], deferred]
              end

  grouped_fk = fk_info.group_by { |row| row["id"] }.values.each { |group| group.sort_by! { |row| row["seq"] } }
  grouped_fk.map do |group|
    row = group.first
    options = {
      on_delete: extract_foreign_key_action(row["on_delete"]),
      on_update: extract_foreign_key_action(row["on_update"]),
      deferrable: fk_defs[[row["table"], row["from"], row["to"]]]
    }

    if group.one?
      options[:column] = row["from"]
      options[:primary_key] = row["to"]
    else
      options[:column] = group.map { |row| row["from"] }
      options[:primary_key] = group.map { |row| row["to"] }
    end
    ForeignKeyDefinition.new(table_name, row["table"], options)
  end
end

rename_table(table_name, new_name, **options)

Renames a table.

Example:

rename_table('octopuses', 'octopi')
Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 359
def rename_table(table_name, new_name, **options)
  validate_table_length!(new_name) unless options[:_uses_legacy_table_name]
  schema_cache.clear_data_source_cache!(table_name.to_s)
  schema_cache.clear_data_source_cache!(new_name.to_s)
  exec_query "ALTER TABLE #{quote_table_name(table_name)} RENAME TO #{quote_table_name(new_name)}"
  rename_table_indexes(table_name, new_name, **options)
end

requires_reloading?()

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 192
def requires_reloading?
  true
end

supports_check_constraints?()

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 200
def supports_check_constraints?
  true
end

supports_common_table_expressions?()

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 216
def supports_common_table_expressions?
  true
end

supports_concurrent_connections?()

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 231
def supports_concurrent_connections?
  !@memory_database
end

supports_datetime_with_precision?()

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 208
def supports_datetime_with_precision?
  true
end

supports_ddl_transactions?()

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 172
def supports_ddl_transactions?
  true
end

supports_deferrable_constraints?()

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 278
def supports_deferrable_constraints?
  true
end

supports_explain?()

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 270
def supports_explain?
  true
end

supports_expression_index?()

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 188
def supports_expression_index?
  true
end

supports_foreign_keys?()

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 196
def supports_foreign_keys?
  true
end

supports_index_sort_order?()

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 261
def supports_index_sort_order?
  true
end

supports_insert_conflict_target?()

Alias for: supports_insert_on_conflict?.

supports_insert_on_conflict?()

Also aliased as: supports_insert_on_duplicate_skip?, supports_insert_on_duplicate_update?, supports_insert_conflict_target?.

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 224
def supports_insert_on_conflict?
  database_version >= "3.24.0"
end

supports_insert_on_duplicate_skip?()

Alias for: supports_insert_on_conflict?.

supports_insert_on_duplicate_update?()

Alias for: supports_insert_on_conflict?.

supports_insert_returning?()

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 220
def supports_insert_returning?
  database_version >= "3.35.0"
end

supports_json?()

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 212
def supports_json?
  true
end

supports_lazy_transactions?()

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 274
def supports_lazy_transactions?
  true
end

supports_partial_index?()

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 184
def supports_partial_index?
  true
end

supports_savepoints?()

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 176
def supports_savepoints?
  true
end

supports_transaction_isolation?()

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 180
def supports_transaction_isolation?
  true
end

supports_views?()

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 204
def supports_views?
  true
end

supports_virtual_columns?()

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 235
def supports_virtual_columns?
  database_version >= "3.31.0"
end

virtual_tables()

Returns a list of defined virtual tables

Source code GitHub 
# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 326
      def virtual_tables
        query = <<~SQL
          SELECT name, sql FROM sqlite_master WHERE sql LIKE 'CREATE VIRTUAL %';
        SQL

        exec_query(query, "SCHEMA").cast_values.each_with_object({}) do |row, memo|
          table_name, sql = row[0], row[1]
          _, module_name, arguments = sql.match(VIRTUAL_TABLE_REGEX).to_a
          memo[table_name] = [module_name, arguments]
        end.to_a
      end

Definition files