method
select_value
rails latest stable - Class:
ActiveRecord::ConnectionAdapters::DatabaseStatements
select_value(arel, name = nil, binds = [], async: false)public
Returns a single value from a record
# File activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb, line 83
def select_value(arel, name = nil, binds = [], async: false)
select_rows(arel, name, binds, async: async).then { |rows| single_value_from_rows(rows) }
end Related methods
- Instance methods
- add_transaction_record
- begin_db_transaction
- begin_isolated_db_transaction
- cacheable_query
- commit_db_transaction
- create
- default_sequence_name
- delete
- empty_insert_statement_value
- exec_delete
- exec_insert
- exec_insert_all
- exec_query
- exec_restart_db_transaction
- exec_rollback_db_transaction
- exec_update
- execute
- explain
- high_precision_current_timestamp
- insert
- insert_fixture
- insert_fixtures_set
- internal_exec_query
- mark_transaction_written_if_write
- query
- query_value
- query_values
- reset_sequence!
- reset_transaction
- restart_db_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?
- truncate
- truncate_tables
- update
- with_yaml_fallback
- write_query?
- Class methods
- new
- Private methods
-
arel_from_relation -
build_fixture_sql -
build_fixture_statements -
build_truncate_statement -
build_truncate_statements -
combine_multi_statements -
default_insert_value -
execute_batch -
extract_table_ref_from_insert_sql -
internal_execute -
last_inserted_id -
raw_execute -
returning_column_values -
select -
single_value_from_rows -
sql_for_insert -
to_sql_and_binds -
with_multi_statements