Class: ActiveRecord::ConnectionAdapters::AbstractMysqlAdapter

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

Direct Known Subclasses

Mysql2Adapter, TrilogyAdapter

Defined Under Namespace

Classes: 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 },
  bigint:      { name: "bigint" },
  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: "boolean" },
  json:        { name: "json" },
}
EXTENDED_TYPE_MAPS = 
Concurrent::Map.new
EMULATE_BOOLEANS_TRUE = 
{ emulate_booleans: true }.freeze

Constants included from MySQL::Quoting

MySQL::Quoting::QUOTED_COLUMN_NAMES, MySQL::Quoting::QUOTED_TABLE_NAMES

Constants inherited from AbstractAdapter

ActiveRecord::ConnectionAdapters::AbstractAdapter::ADAPTER_NAME, ActiveRecord::ConnectionAdapters::AbstractAdapter::COMMENT_REGEX, ActiveRecord::ConnectionAdapters::AbstractAdapter::MAX_JITTER, ActiveRecord::ConnectionAdapters::AbstractAdapter::SIMPLE_INT, ActiveRecord::ConnectionAdapters::AbstractAdapter::TYPE_MAP

Constants included from QueryCache

QueryCache::DEFAULT_SIZE

Instance Attribute Summary

Attributes inherited from AbstractAdapter

#allow_preconnect, #lock, #logger, #owner, #pinned, #pool, #visitor

Attributes included from QueryCache

#query_cache

Attributes included from DatabaseStatements

#transaction_manager

Class Method Summary collapse

Instance Method Summary collapse

Methods included from MySQL::SchemaStatements

#add_index_options, #create_index_definition, #create_schema_dumper, #create_table, #indexes, #internal_string_options_for_primary_key, #remove_column, #remove_foreign_key, #schema_creation, #table_alias_length, #type_to_sql, #update_table_definition

Methods included from MySQL::Quoting

#cast_bound_value, #quoted_binary, #type_cast, #unquote_identifier, #unquoted_false, #unquoted_true

Methods included from MySQL::DatabaseStatements

#build_explain_clause, #default_insert_value, #explain, #high_precision_current_timestamp, #write_query?

Methods inherited from AbstractAdapter

#active?, #adapter_name, #add_enum_value, #advisory_locks_enabled?, #async_enabled?, build_read_query_regexp, #case_insensitive_comparison, #check_all_foreign_keys_valid!, #clean!, #clear_cache!, #close, #connect!, #connected?, #connection_age, #connection_descriptor, #connection_retries, #create_enum, #create_virtual_table, database_exists?, #database_exists?, #database_version, #default_timezone, #default_uniqueness_comparison, #disable_extension, #discard!, #disconnect!, #drop_enum, #drop_virtual_table, #enable_extension, #ensure_writes_are_allowed, #expire, #extensions, find_cmd_and_exec, #force_retirement, #initialize, #inspect, #lease, #lock_thread=, #max_jitter, #native_database_types, #pool_jitter, #prefetch_primary_key?, #prepared_statements?, #prepared_statements_disabled_cache, #preventing_writes?, #raw_connection, #reconnect!, register_class_with_precision, #rename_enum, #rename_enum_value, #replica?, #requires_reloading?, #reset!, #retry_deadline, #role, #savepoint_errors_invalidate_transactions?, #schema_cache, #schema_version, #seconds_idle, #seconds_since_last_activity, #shard, #steal!, #supports_comments?, #supports_comments_in_create?, #supports_concurrent_connections?, #supports_ddl_transactions?, #supports_deferrable_constraints?, #supports_exclusion_constraints?, #supports_extensions?, #supports_foreign_tables?, #supports_index_include?, #supports_insert_conflict_target?, #supports_json?, #supports_lazy_transactions?, #supports_materialized_views?, #supports_nulls_not_distinct?, #supports_partial_index?, #supports_partitioned_indexes?, #supports_savepoints?, #supports_unique_constraints?, #supports_validate_constraints?, #throw_away!, type_cast_config_to_boolean, type_cast_config_to_integer, #unprepared_statement, #valid_type?, valid_type?, validate_default_timezone, #verified?, #verify!, #verify_timeout

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, #initialize, #query_cache_enabled, #select_all, #uncached

Methods included from DatabaseLimits

#index_name_length, #max_identifier_length, #table_alias_length, #table_name_length

Methods included from Quoting

#cast_bound_value, #lookup_cast_type, #quote, #quote_column_name, #quote_default_expression, #quote_table_name, #quote_table_name_for_assignment, #quoted_binary, #quoted_date, #quoted_false, #quoted_time, #quoted_true, #sanitize_as_sql_comment, #type_cast, #unquoted_false, #unquoted_true

Methods included from DatabaseStatements

#add_transaction_record, #begin_deferred_transaction, #cacheable_query, #default_insert_value, #default_sequence_name, #delete, #exec_delete, #exec_insert, #exec_insert_all, #exec_query, #exec_update, #execute, #explain, #high_precision_current_timestamp, #initialize, #insert, #insert_fixture, #insert_fixtures_set, #internal_exec_query, #mark_transaction_written, #query, #query_value, #query_values, #raw_exec_query, #reset_isolation_level, #reset_sequence!, #reset_transaction, #restart_db_transaction, #rollback_db_transaction, #rollback_to_savepoint, #select_all, #select_one, #select_rows, #select_value, #select_values, #to_sql, #transaction, #transaction_isolation_levels, #transaction_open?, #truncate, #truncate_tables, #update, #with_yaml_fallback, #write_query?

Methods included from SchemaStatements

#add_check_constraint, #add_column, #add_columns, #add_foreign_key, #add_index_options, #add_reference, #add_timestamps, #assume_migrated_upto_version, #build_add_column_definition, #build_create_join_table_definition, #build_create_table_definition, #bulk_change_table, #change_table, #check_constraint_exists?, #check_constraint_options, #column_exists?, #columns, #create_join_table, #create_schema_dumper, #create_table, #data_source_exists?, #data_sources, #distinct_relation_for_primary_key, #drop_join_table, #dump_schema_versions, #foreign_key_column_for, #foreign_key_exists?, #foreign_key_options, #index_algorithm, #index_exists?, #index_name, #index_name_exists?, #indexes, #internal_string_options_for_primary_key, #max_index_name_size, #native_database_types, #options_include_default?, #primary_key, #quoted_columns_for_index, #remove_check_constraint, #remove_column, #remove_columns, #remove_constraint, #remove_foreign_key, #remove_index, #remove_reference, #remove_timestamps, #schema_creation, #table_alias_for, #table_exists?, #tables, #type_to_sql, #update_table_definition, #use_foreign_keys?, #valid_column_definition_options, #valid_primary_key_options, #valid_table_definition_options, #view_exists?, #views

Constructor Details

This class inherits a constructor from ActiveRecord::ConnectionAdapters::AbstractAdapter

Class Method Details

.dbconsole(config, options = {}) ⇒ Object 



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 57

def dbconsole(config, options = {})
  mysql_config = config.configuration_hash

  args = {
    host: "--host",
    port: "--port",
    socket: "--socket",
    username: "--user",
    encoding: "--default-character-set",
    sslca: "--ssl-ca",
    sslcert: "--ssl-cert",
    sslcapath: "--ssl-capath",
    sslcipher: "--ssl-cipher",
    sslkey: "--ssl-key",
    ssl_mode: "--ssl-mode"
  }.filter_map { |opt, arg| "#{arg}=#{mysql_config[opt]}" if mysql_config[opt] }

  if mysql_config[:password] && options[:include_password]
    args << "--password=#{mysql_config[:password]}"
  elsif mysql_config[:password] && !mysql_config[:password].to_s.empty?
    args << "-p"
  end

  args << config.database

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

.extended_type_map(default_timezone: nil, emulate_booleans:) ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 728

def extended_type_map(default_timezone: nil, emulate_booleans:) # :nodoc:
  super(default_timezone: default_timezone).tap do |m|
    if emulate_booleans
      m.register_type %r(^tinyint\(1\))i, Type::Boolean.new
    end
  end
end

.native_database_types ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 85

def native_database_types # :nodoc:
  NATIVE_DATABASE_TYPES
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 453

def add_index(table_name, column_name, **options) # :nodoc:
  create_index = build_create_index_definition(table_name, column_name, **options)
  return unless create_index

  execute schema_creation.accept(create_index)
end

#add_sql_comment!(sql, comment) ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 486

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

#begin_db_transaction ⇒ Object

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



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 235

def begin_db_transaction # :nodoc:
  internal_execute("BEGIN", "TRANSACTION", allow_retry: true, materialize_transactions: false)
end

#begin_isolated_db_transaction(isolation) ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 239

def begin_isolated_db_transaction(isolation) # :nodoc:
  # From MySQL manual: The [SET TRANSACTION] statement applies only to the next single transaction performed within the session.
  # So we don't need to implement #reset_isolation_level
  execute_batch(
    ["SET TRANSACTION ISOLATION LEVEL #{transaction_isolation_levels.fetch(isolation)}", "BEGIN"],
    "TRANSACTION",
    allow_retry: true,
    materialize_transactions: false,
  )
end

#build_change_column_default_definition(table_name, column_name, default_or_changes) ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 381

def build_change_column_default_definition(table_name, column_name, default_or_changes) # :nodoc:
  column = column_for(table_name, column_name)
  return unless column

  default = extract_new_default_value(default_or_changes)
  ChangeColumnDefaultDefinition.new(column, default)
end

#build_change_column_definition(table_name, column_name, type, **options) ⇒ Object

Builds a ChangeColumnDefinition object.

This definition object contains information about the column change that would occur if the same arguments were passed to #change_column. See #change_column for information about passing a table_name, column_name, type and other options that can be passed.



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 413

def build_change_column_definition(table_name, column_name, type, **options) # :nodoc:
  column = column_for(table_name, column_name)
  type ||= column.sql_type

  unless options.key?(:default)
    options[:default] = if column.default_function
      -> { column.default_function }
    else
      column.default
    end
  end

  unless options.key?(:null)
    options[:null] = column.null
  end

  unless options.key?(:comment)
    options[:comment] = column.comment
  end

  if options[:collation] == :no_collation
    options.delete(:collation)
  else
    options[:collation] ||= column.collation if text_type?(type)
  end

  unless options.key?(:auto_increment)
    options[:auto_increment] = column.auto_increment?
  end

  td = create_table_definition(table_name)
  cd = td.new_column_definition(column.name, type, **options)
  ChangeColumnDefinition.new(cd, column.name)
end

#build_create_index_definition(table_name, column_name, **options) ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 460

def build_create_index_definition(table_name, column_name, **options) # :nodoc:
  index, algorithm, if_not_exists = add_index_options(table_name, column_name, **options)

  return if if_not_exists && index_exists?(table_name, column_name, name: index.name)

  CreateIndexDefinition.new(index, algorithm)
end

#build_insert_sql(insert) ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 664

def build_insert_sql(insert) # :nodoc:
  # Can use any column as it will be assigned to itself.
  no_op_column = quote_column_name(insert.keys.first) if insert.keys.first

  # MySQL 8.0.19 replaces `VALUES(<expression>)` clauses with row and column alias names, see https://dev.mysql.com/worklog/task/?id=6312 .
  # then MySQL 8.0.20 deprecates the `VALUES(<expression>)` see https://dev.mysql.com/worklog/task/?id=13325 .
  if supports_insert_raw_alias_syntax?
    quoted_table_name = insert.model.quoted_table_name
    values_alias = quote_table_name("#{insert.model.table_name.parameterize}_values")
    sql = +"INSERT #{insert.into} #{insert.values_list} AS #{values_alias}"

    if insert.skip_duplicates?
      if no_op_column
        sql << " ON DUPLICATE KEY UPDATE #{no_op_column}=#{quoted_table_name}.#{no_op_column}"
      end
    elsif insert.update_duplicates?
      if insert.raw_update_sql?
        sql = +"INSERT #{insert.into} #{insert.values_list} ON DUPLICATE KEY UPDATE #{insert.raw_update_sql}"
      else
        sql << " ON DUPLICATE KEY UPDATE "
        sql << insert.touch_model_timestamps_unless { |column| "#{quoted_table_name}.#{column}<=>#{values_alias}.#{column}" }
        sql << insert.updatable_columns.map { |column| "#{column}=#{values_alias}.#{column}" }.join(",")
      end
    end
  else
    sql = +"INSERT #{insert.into} #{insert.values_list}"

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

  sql << " RETURNING #{insert.returning}" if insert.returning
  sql
end

#case_sensitive_comparison(attribute, value) ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 626

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 404

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 399

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 377

def change_column_default(table_name, column_name, default_or_changes) # :nodoc:
  execute "ALTER TABLE #{quote_table_name(table_name)} #{change_column_default_for_alter(table_name, column_name, default_or_changes)}"
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 389

def change_column_null(table_name, column_name, null, default = nil) # :nodoc:
  validate_change_column_null_argument!(null)

  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 329

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 309

def charset
  show_variable "character_set_database"
end

#check_constraints(table_name) ⇒ Object 



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 536

def check_constraints(table_name)
  if supports_check_constraints?
    scope = quoted_scope(table_name)

    sql = <<~SQL
      SELECT cc.constraint_name AS 'name',
            cc.check_clause AS 'expression'
      FROM information_schema.check_constraints cc
      JOIN information_schema.table_constraints tc
      USING (constraint_schema, constraint_name)
      WHERE tc.table_schema = #{scope[:schema]}
        AND tc.table_name = #{scope[:name]}
        AND cc.constraint_schema = #{scope[:schema]}
    SQL
    sql += " AND cc.table_name = #{scope[:name]}" if mariadb?

    chk_info = internal_exec_query(sql, "SCHEMA")

    chk_info.map do |row|
      options = {
        name: row["name"]
      }
      expression = row["expression"]
      expression = expression[1..-2] if expression.start_with?("(") && expression.end_with?(")")
      expression = strip_whitespace_characters(expression)

      unless mariadb?
        # MySQL returns check constraints expression in an already escaped form.
        # This leads to duplicate escaping later (e.g. when the expression is used in the SchemaDumper).
        expression = expression.gsub("\\'", "'")
      end

      CheckConstraintDefinition.new(table_name, expression, options)
    end
  else
    raise NotImplementedError
  end
end

#check_version ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 710

def check_version # :nodoc:
  if database_version < "5.6.4"
    raise DatabaseVersionError, "Your version of MySQL (#{database_version}) is too old. Active Record supports MySQL >= 5.6.4."
  end
end

#collation ⇒ Object

Returns the database collation strategy.



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 314

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/en/group-by-handling.html



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 645

def columns_for_distinct(columns, orders) # :nodoc:
  order_columns = orders.compact_blank.map { |s|
    # Convert Arel node to string
    s = visitor.compile(s) unless s.is_a?(String)
    # Remove any ASC/DESC modifiers
    s.gsub(/\s+(?:ASC|DESC)\b/i, "")
  }.compact_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 250

def commit_db_transaction # :nodoc:
  internal_execute("COMMIT", "TRANSACTION", allow_retry: false, materialize_transactions: true)
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 284

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 304

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 660

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

#disable_index(table_name, index_name) ⇒ Object

:nodoc:

Raises:

  • (NotImplementedError) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 477

def disable_index(table_name, index_name) # :nodoc:
  raise NotImplementedError unless supports_disabling_indexes?

  query = <<~SQL
    ALTER TABLE #{quote_table_name(table_name)} ALTER INDEX #{index_name} #{mariadb? ? "IGNORED" : "INVISIBLE"}
  SQL
  execute(query)
end

#disable_referential_integrity ⇒ Object

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



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 220

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}") if active?
  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 300

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

#drop_table(*table_names, **options) ⇒ Object

Drops a table or tables 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 except if you provide more than one table which is not supported.



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 362

def drop_table(*table_names, **options)
  table_names.each { |table_name| schema_cache.clear_data_source_cache!(table_name.to_s) }
  execute "DROP#{' TEMPORARY' if options[:temporary]} TABLE#{' IF EXISTS' if options[:if_exists]} #{table_names.map { |table_name| quote_table_name(table_name) }.join(', ')}#{' CASCADE' if options[:force] == :cascade}"
end

#empty_insert_statement_value(primary_key = nil) ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 262

def empty_insert_statement_value(primary_key = nil) # :nodoc:
  "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 29

class_attribute :emulate_booleans, default: true

#enable_index(table_name, index_name) ⇒ Object

:nodoc:

Raises:

  • (NotImplementedError) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 468

def enable_index(table_name, index_name) # :nodoc:
  raise NotImplementedError unless supports_disabling_indexes?

  query = <<~SQL
    ALTER TABLE #{quote_table_name(table_name)} ALTER INDEX #{index_name} #{mariadb? ? "NOT IGNORED" : "VISIBLE"}
  SQL
  execute(query)
end

#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 214

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

#exec_restart_db_transaction ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 258

def exec_restart_db_transaction # :nodoc:
  internal_execute("ROLLBACK AND CHAIN", "TRANSACTION", allow_retry: false, materialize_transactions: true)
end

#exec_rollback_db_transaction ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 254

def exec_rollback_db_transaction # :nodoc:
  internal_execute("ROLLBACK", "TRANSACTION", allow_retry: false, materialize_transactions: true)
end

#foreign_keys(table_name) ⇒ Object

Raises:

  • (ArgumentError) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 491

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

  scope = quoted_scope(table_name)

  # MySQL returns 1 row for each column of composite foreign keys.
  fk_info = internal_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',
           fk.ordinal_position AS 'position',
           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

  grouped_fk = fk_info.group_by { |row| row["name"] }.values.each { |group| group.sort_by! { |row| row["position"] } }
  grouped_fk.map do |group|
    row = group.first
    options = {
      name: row["name"],
      on_update: extract_foreign_key_action(row["on_update"]),
      on_delete: extract_foreign_key_action(row["on_delete"])
    }

    if group.one?
      options[:column] = unquote_identifier(row["column"])
      options[:primary_key] = row["primary_key"]
    else
      options[:column] = group.map { |row| unquote_identifier(row["column"]) }
      options[:primary_key] = group.map { |row| row["primary_key"] }
    end

    ForeignKeyDefinition.new(table_name, unquote_identifier(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 195

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 90

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 203

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

#mariadb? ⇒ Boolean

:nodoc:

Returns:

  • (Boolean) 


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

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

#primary_keys(table_name) ⇒ Object

:nodoc:

Raises:

  • (ArgumentError) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 611

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.statistics
    WHERE index_name = 'PRIMARY'
      AND table_schema = #{scope[:schema]}
      AND table_name = #{scope[:name]}
    ORDER BY seq_in_index
  SQL
end

#quote_string(string) ⇒ Object

Quotes strings for use in SQL input.



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 721

def quote_string(string)
  with_raw_connection(allow_retry: true, materialize_transactions: false) do |connection|
    connection.escape(string)
  end
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 270

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 199

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 448

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 367

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, **options) ⇒ Object

Renames a table.

Example:

rename_table('octopuses', 'octopi')



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

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

#return_value_after_insert?(column) ⇒ Boolean

:nodoc:

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 181

def return_value_after_insert?(column) # :nodoc:
  supports_insert_returning? ? column.auto_populated? : column.auto_increment?
end

#show_variable(name) ⇒ Object

SHOW VARIABLES LIKE ‘name’



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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 605

def show_variable(name)
  query_value("SELECT @@#{name}", "SCHEMA", materialize_transactions: false, allow_retry: true)
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 656

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 165

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 100

def supports_bulk_alter?
  true
end

#supports_check_constraints? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 132

def supports_check_constraints?
  if mariadb?
    database_version >= "10.3.10" || (database_version < "10.3" && database_version >= "10.2.22")
  else
    database_version >= "8.0.16"
  end
end

#supports_common_table_expressions? ⇒ Boolean

Returns:

  • (Boolean) 


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

def supports_common_table_expressions?
  if mariadb?
    database_version >= "10.2.1"
  else
    database_version >= "8.0.1"
  end
end

#supports_datetime_with_precision? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 144

def supports_datetime_with_precision?
  true
end

#supports_disabling_indexes? ⇒ Boolean

See dev.mysql.com/doc/refman/8.0/en/invisible-indexes.html for more details on MySQL feature. See mariadb.com/kb/en/ignored-indexes/ for more details on the MariaDB feature.

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 187

def supports_disabling_indexes?
  if mariadb?
    database_version >= "10.6.0"
  else
    database_version >= "8.0.0"
  end
end

#supports_explain? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 120

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 108

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 128

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 104

def supports_index_sort_order?
  mariadb? ? database_version >= "10.8.1" : 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 124

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 169

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 173

def supports_insert_on_duplicate_update?
  true
end

#supports_insert_returning? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 177

def supports_insert_returning?
  mariadb? && database_version >= "10.5.0"
end

#supports_optimizer_hints? ⇒ Boolean

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

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 153

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

#supports_restart_db_transaction? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 116

def supports_restart_db_transaction?
  true
end

#supports_transaction_isolation? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/abstract_mysql_adapter.rb', line 112

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 140

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 148

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 318

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 575

def table_options(table_name) # :nodoc:
  create_table_info = create_table_info(table_name)

  # strip create_definitions and partition_options
  # Be aware that `create_table_info` might not include any table options due to `NO_TABLE_OPTIONS` sql mode.
  raw_table_options = create_table_info.sub(/\A.*\n\) ?/m, "").sub(/\n\/\*!.*\*\/\n\z/m, "").strip

  return if raw_table_options.empty?

  table_options = {}

  if / DEFAULT CHARSET=(?<charset>\w+)(?: COLLATE=(?<collation>\w+))?/ =~ raw_table_options
    raw_table_options = $` + $' # before part + after part
    table_options[:charset] = charset
    table_options[:collation] = collation if collation
  end

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

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

  table_options[:options] = raw_table_options unless raw_table_options == "ENGINE=InnoDB"
  table_options
end