module ActiveRecord::ConnectionAdapters::PostgreSQL::SchemaStatements
Public Instance Methods
Returns the current client message level.
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 243 def client_min_messages query_value("SHOW client_min_messages", "SCHEMA") end
Set the client message level.
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 248 def client_min_messages=(level) execute("SET client_min_messages TO '#{level}'", "SCHEMA") end
Returns the current database collation.
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 195 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 activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 24 def create_database(name, options = {}) options = { encoding: "utf8" }.merge!(options.symbolize_keys) option_string = options.inject("") do |memo, (key, value)| 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 activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 216 def create_schema(schema_name) execute "CREATE SCHEMA #{quote_schema_name(schema_name)}" end
Returns the current database ctype.
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 200 def ctype query_value("SELECT datctype FROM pg_database WHERE datname = current_database()", "SCHEMA") end
Returns the current database name.
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 180 def current_database query_value("SELECT current_database()", "SCHEMA") end
Returns the current schema name.
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 185 def current_schema query_value("SELECT current_schema", "SCHEMA") end
Drops the schema for the given schema name.
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 221 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 activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 190 def encoding query_value("SELECT pg_encoding_to_char(encoding) FROM pg_database WHERE datname = current_database()", "SCHEMA") end
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 512 def foreign_keys(table_name) scope = quoted_scope(table_name) fk_info = exec_query(<<-SQL.strip_heredoc, "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 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"]) ForeignKeyDefinition.new(table_name, row["to_table"], options) end end
Verifies existence of an index with a given name.
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 69 def index_name_exists?(table_name, index_name, default = nil) unless default.nil? ActiveSupport::Deprecation.warn(<<-MSG.squish) Passing default to #index_name_exists? is deprecated without replacement. MSG end 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 = '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 activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 506 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 activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 384 def rename_table(table_name, new_name) clear_cache! 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 activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 64 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 activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 205 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 activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 238 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 activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 230 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 activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 261 def serial_sequence(table, column) query_value("SELECT pg_get_serial_sequence(#{quote(table)}, #{quote(column)})", "SCHEMA") end
Private Instance Methods
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 602 def create_table_definition(*args) PostgreSQL::TableDefinition.new(*args) end
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 644 def data_source_sql(name = nil, type: nil) scope = quoted_scope(name, type: type) scope[:type] ||= "'r','v','m'" # (r)elation/table, (v)iew, (m)aterialized view sql = "SELECT c.relname FROM pg_class c LEFT JOIN pg_namespace n ON n.oid = c.relnamespace".dup 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 activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 636 def extract_foreign_key_action(specifier) case specifier when "c"; :cascade when "n"; :nullify when "r"; :restrict end end
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 671 def extract_schema_qualified_name(string) name = Utils.extract_schema_qualified_name(string.to_s) [name.schema, name.identifier] end
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 624 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, ) PostgreSQLTypeMetadata.new(simple_type, oid: oid, fmod: fmod) end
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 606 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) PostgreSQLColumn.new( column_name, default_value, type_metadata, !notnull, table_name, default_function, collation, comment: comment.presence ) end
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 655 def quoted_scope(name = nil, type: nil) schema, name = extract_schema_qualified_name(name) type = \ case type when "BASE TABLE" "'r'" when "VIEW" "'v','m'" 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 activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 598 def schema_creation PostgreSQL::SchemaCreation.new(self) end