module ActiveRecord::ConnectionAdapters::PostgreSQL::SchemaStatements
Public Instance Methods
Returns the current client message level.
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 237 def client_min_messages query_value("SHOW client_min_messages", "SCHEMA") end
Set the client message level.
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 242 def client_min_messages=(level) execute("SET client_min_messages TO '#{level}'", "SCHEMA") end
Returns the current database collation.
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 189 def collation query_value("SELECT datcollate FROM pg_database WHERE datname = current_database()", "SCHEMA") end
Create a new PostgreSQL database. Options include :owner
, :template
, :encoding
(defaults to utf8), :collation
, :ctype
, :tablespace
, and :connection_limit
(note that MySQL
uses :charset
while PostgreSQL uses :encoding
).
Example:
create_database config[:database], config create_database 'foo_development', encoding: 'unicode'
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 22 def create_database(name, options = {}) options = { encoding: "utf8" }.merge!(options.symbolize_keys) option_string = options.each_with_object(+"") do |(key, value), memo| memo << case key when :owner " OWNER = \"#{value}\"" when :template " TEMPLATE = \"#{value}\"" when :encoding " ENCODING = '#{value}'" when :collation " LC_COLLATE = '#{value}'" when :ctype " LC_CTYPE = '#{value}'" when :tablespace " TABLESPACE = \"#{value}\"" when :connection_limit " CONNECTION LIMIT = #{value}" else "" end end execute "CREATE DATABASE #{quote_table_name(name)}#{option_string}" end
Creates a schema for the given schema name.
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 210 def create_schema(schema_name) execute "CREATE SCHEMA #{quote_schema_name(schema_name)}" end
Returns the current database ctype.
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 194 def ctype query_value("SELECT datctype FROM pg_database WHERE datname = current_database()", "SCHEMA") end
Returns the current database name.
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 174 def current_database query_value("SELECT current_database()", "SCHEMA") end
Returns the current schema name.
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 179 def current_schema query_value("SELECT current_schema", "SCHEMA") end
Drops the schema for the given schema name.
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 215 def drop_schema(schema_name, **options) execute "DROP SCHEMA#{' IF EXISTS' if options[:if_exists]} #{quote_schema_name(schema_name)} CASCADE" end
Returns the current database encoding format.
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 184 def encoding query_value("SELECT pg_encoding_to_char(encoding) FROM pg_database WHERE datname = current_database()", "SCHEMA") end
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 483 def foreign_keys(table_name) scope = quoted_scope(table_name) fk_info = exec_query(<<~SQL, "SCHEMA") SELECT t2.oid::regclass::text AS to_table, a1.attname AS column, a2.attname AS primary_key, c.conname AS name, c.confupdtype AS on_update, c.confdeltype AS on_delete, c.convalidated AS valid FROM pg_constraint c JOIN pg_class t1 ON c.conrelid = t1.oid JOIN pg_class t2 ON c.confrelid = t2.oid JOIN pg_attribute a1 ON a1.attnum = c.conkey[1] AND a1.attrelid = t1.oid JOIN pg_attribute a2 ON a2.attnum = c.confkey[1] AND a2.attrelid = t2.oid JOIN pg_namespace t3 ON c.connamespace = t3.oid WHERE c.contype = 'f' AND t1.relname = #{scope[:name]} AND t3.nspname = #{scope[:schema]} ORDER BY c.conname SQL fk_info.map do |row| options = { column: row["column"], name: row["name"], primary_key: row["primary_key"] } options[:on_delete] = extract_foreign_key_action(row["on_delete"]) options[:on_update] = extract_foreign_key_action(row["on_update"]) options[:validate] = row["valid"] ForeignKeyDefinition.new(table_name, row["to_table"], options) end end
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 518 def foreign_table_exists?(table_name) query_values(data_source_sql(table_name, type: "FOREIGN TABLE"), "SCHEMA").any? if table_name.present? end
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 514 def foreign_tables query_values(data_source_sql(type: "FOREIGN TABLE"), "SCHEMA") end
Verifies existence of an index with a given name.
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 68 def index_name_exists?(table_name, index_name) table = quoted_scope(table_name) index = quoted_scope(index_name) query_value(<<~SQL, "SCHEMA").to_i > 0 SELECT COUNT(*) FROM pg_class t INNER JOIN pg_index d ON t.oid = d.indrelid INNER JOIN pg_class i ON d.indexrelid = i.oid LEFT JOIN pg_namespace n ON n.oid = i.relnamespace WHERE i.relkind IN ('i', 'I') AND i.relname = #{index[:name]} AND t.relname = #{table[:name]} AND n.nspname = #{index[:schema]} SQL end
Renames an index of a table. Raises error if length of new index name is greater than allowed limit.
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 477 def rename_index(table_name, old_name, new_name) validate_index_length!(table_name, new_name) execute "ALTER INDEX #{quote_column_name(old_name)} RENAME TO #{quote_table_name(new_name)}" end
Renames a table. Also renames a table's primary key sequence if the sequence name exists and matches the Active Record default.
Example:
rename_table('octopuses', 'octopi')
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 378 def rename_table(table_name, new_name) clear_cache! schema_cache.clear_data_source_cache!(table_name.to_s) schema_cache.clear_data_source_cache!(new_name.to_s) execute "ALTER TABLE #{quote_table_name(table_name)} RENAME TO #{quote_table_name(new_name)}" pk, seq = pk_and_sequence_for(new_name) if pk idx = "#{table_name}_pkey" new_idx = "#{new_name}_pkey" execute "ALTER INDEX #{quote_table_name(idx)} RENAME TO #{quote_table_name(new_idx)}" if seq && seq.identifier == "#{table_name}_#{pk}_seq" new_seq = "#{new_name}_#{pk}_seq" execute "ALTER TABLE #{seq.quoted} RENAME TO #{quote_table_name(new_seq)}" end end rename_table_indexes(table_name, new_name) end
Returns true if schema exists.
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 63 def schema_exists?(name) query_value("SELECT COUNT(*) FROM pg_namespace WHERE nspname = #{quote(name)}", "SCHEMA").to_i > 0 end
Returns an array of schema names.
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 199 def schema_names query_values(<<~SQL, "SCHEMA") SELECT nspname FROM pg_namespace WHERE nspname !~ '^pg_.*' AND nspname NOT IN ('information_schema') ORDER by nspname; SQL end
Returns the active schema search path.
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 232 def schema_search_path @schema_search_path ||= query_value("SHOW search_path", "SCHEMA") end
Sets the schema search path to a string of comma-separated schema names. Names beginning with $ have to be quoted (e.g. $user => '$user'). See: www.postgresql.org/docs/current/static/ddl-schemas.html
This should be not be called manually but set in database.yml.
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 224 def schema_search_path=(schema_csv) if schema_csv execute("SET search_path TO #{schema_csv}", "SCHEMA") @schema_search_path = schema_csv end end
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 255 def serial_sequence(table, column) query_value("SELECT pg_get_serial_sequence(#{quote(table)}, #{quote(column)})", "SCHEMA") end
Validates the given check constraint.
validate_check_constraint :products, name: "price_check"
The options
hash accepts the same keys as add_check_constraint.
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 637 def validate_check_constraint(table_name, **options) chk_name_to_validate = check_constraint_for!(table_name, **options).name validate_constraint table_name, chk_name_to_validate end
Validates the given constraint.
Validates the constraint named constraint_name
on accounts
.
validate_constraint :accounts, :constraint_name
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 604 def validate_constraint(table_name, constraint_name) at = create_alter_table table_name at.validate_constraint constraint_name execute schema_creation.accept(at) end
Validates the given foreign key.
Validates the foreign key on accounts.branch_id
.
validate_foreign_key :accounts, :branches
Validates the foreign key on accounts.owner_id
.
validate_foreign_key :accounts, column: :owner_id
Validates the foreign key named special_fk_name
on the accounts
table.
validate_foreign_key :accounts, name: :special_fk_name
The options
hash accepts the same keys as SchemaStatements#add_foreign_key.
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 626 def validate_foreign_key(from_table, to_table = nil, **options) fk_name_to_validate = foreign_key_for!(from_table, to_table: to_table, **options).name validate_constraint from_table, fk_name_to_validate end
Private Instance Methods
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 714 def add_column_for_alter(table_name, column_name, type, **options) return super unless options.key?(:comment) [super, Proc.new { change_column_comment(table_name, column_name, options[:comment]) }] end
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 746 def add_index_opclass(quoted_columns, **options) opclasses = options_for_index_columns(options[:opclass]) quoted_columns.each do |name, column| column << " #{opclasses[name]}" if opclasses[name].present? end end
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 753 def add_options_for_index_columns(quoted_columns, **options) quoted_columns = add_index_opclass(quoted_columns, **options) super end
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 727 def change_column_default_for_alter(table_name, column_name, default_or_changes) column = column_for(table_name, column_name) return unless column default = extract_new_default_value(default_or_changes) alter_column_query = "ALTER COLUMN #{quote_column_name(column_name)} %s" if default.nil? # <tt>DEFAULT NULL</tt> results in the same behavior as <tt>DROP DEFAULT</tt>. However, PostgreSQL will # cast the default to the columns type, which leaves us with a default like "default NULL::character varying". alter_column_query % "DROP DEFAULT" else alter_column_query % "SET DEFAULT #{quote_default_expression(default, column)}" end end
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 719 def change_column_for_alter(table_name, column_name, type, **options) td = create_table_definition(table_name) cd = td.new_column_definition(column_name, type, **options) sqls = [schema_creation.accept(ChangeColumnDefinition.new(cd, column_name))] sqls << Proc.new { change_column_comment(table_name, column_name, options[:comment]) } if options.key?(:comment) sqls end
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 742 def change_column_null_for_alter(table_name, column_name, null, default = nil) "ALTER COLUMN #{quote_column_name(column_name)} #{null ? 'DROP' : 'SET'} NOT NULL" end
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 652 def create_alter_table(name) PostgreSQL::AlterTable.new create_table_definition(name) end
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 648 def create_table_definition(name, **options) PostgreSQL::TableDefinition.new(self, name, **options) end
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 758 def data_source_sql(name = nil, type: nil) scope = quoted_scope(name, type: type) scope[:type] ||= "'r','v','m','p','f'" # (r)elation/table, (v)iew, (m)aterialized view, (p)artitioned table, (f)oreign table sql = +"SELECT c.relname FROM pg_class c LEFT JOIN pg_namespace n ON n.oid = c.relnamespace" sql << " WHERE n.nspname = #{scope[:schema]}" sql << " AND c.relname = #{scope[:name]}" if scope[:name] sql << " AND c.relkind IN (#{scope[:type]})" sql end
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 706 def extract_foreign_key_action(specifier) case specifier when "c"; :cascade when "n"; :nullify when "r"; :restrict end end
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 787 def extract_schema_qualified_name(string) name = Utils.extract_schema_qualified_name(string.to_s) [name.schema, name.identifier] end
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 678 def fetch_type_metadata(column_name, sql_type, oid, fmod) cast_type = get_oid_type(oid, fmod, column_name, sql_type) simple_type = SqlTypeMetadata.new( sql_type: sql_type, type: cast_type.type, limit: cast_type.limit, precision: cast_type.precision, scale: cast_type.scale, ) PostgreSQL::TypeMetadata.new(simple_type, oid: oid, fmod: fmod) end
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 656 def new_column_from_field(table_name, field) column_name, type, default, notnull, oid, fmod, collation, comment = field type_metadata = fetch_type_metadata(column_name, type, oid.to_i, fmod.to_i) default_value = extract_value_from_default(default) default_function = extract_default_function(default_value, default) if match = default_function&.match(/\Anextval\('"?(?<sequence_name>.+_(?<suffix>seq\d*))"?'::regclass\)\z/) serial = sequence_name_from_parts(table_name, column_name, match[:suffix]) == match[:sequence_name] end PostgreSQL::Column.new( column_name, default_value, type_metadata, !notnull, default_function, collation: collation, comment: comment.presence, serial: serial ) end
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 769 def quoted_scope(name = nil, type: nil) schema, name = extract_schema_qualified_name(name) type = \ case type when "BASE TABLE" "'r','p'" when "VIEW" "'v','m'" when "FOREIGN TABLE" "'f'" end scope = {} scope[:schema] = schema ? quote(schema) : "ANY (current_schemas(false))" scope[:name] = quote(name) if name scope[:type] = type if type scope end
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 644 def schema_creation PostgreSQL::SchemaCreation.new(self) end
# File lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 690 def sequence_name_from_parts(table_name, column_name, suffix) over_length = [table_name, column_name, suffix].sum(&:length) + 2 - max_identifier_length if over_length > 0 column_name_length = [(max_identifier_length - suffix.length - 2) / 2, column_name.length].min over_length -= column_name.length - column_name_length column_name = column_name[0, column_name_length - [over_length, 0].min] end if over_length > 0 table_name = table_name[0, table_name.length - over_length] end "#{table_name}_#{column_name}_#{suffix}" end