Class: ActiveRecord::ConnectionAdapters::PostgreSQLAdapter
- Inherits:
-
AbstractAdapter
- Object
- AbstractAdapter
- ActiveRecord::ConnectionAdapters::PostgreSQLAdapter
- Defined in:
- lib/active_record/connection_adapters/postgresql_adapter.rb
Overview
The PostgreSQL adapter works both with the native C (ruby.scripting.ca/postgres/) and the pure Ruby (available both as gem and from rubyforge.org/frs/?group_id=234&release_id=1944) drivers.
Options:
-
:host
- Defaults to “localhost”. -
:port
- Defaults to 5432. -
:username
- Defaults to nothing. -
:password
- Defaults to nothing. -
:database
- The name of the database. No default, must be provided. -
:schema_search_path
- An optional schema search path for the connection given as a string of comma-separated schema names. This is backward-compatible with the:schema_order
option. -
:encoding
- An optional client encoding that is used in aSET client_encoding TO <encoding>
call on the connection. -
:min_messages
- An optional client min messages that is used in aSET client_min_messages TO <min_messages>
call on the connection. -
:allow_concurrency
- If true, use async query methods so Ruby threads don’t deadlock; otherwise, use blocking query methods.
Constant Summary collapse
- ADAPTER_NAME =
'PostgreSQL'.freeze
- NATIVE_DATABASE_TYPES =
{ :primary_key => "serial primary key".freeze, :string => { :name => "character varying", :limit => 255 }, :text => { :name => "text" }, :integer => { :name => "integer" }, :float => { :name => "float" }, :decimal => { :name => "decimal" }, :datetime => { :name => "timestamp" }, :timestamp => { :name => "timestamp" }, :time => { :name => "time" }, :date => { :name => "date" }, :binary => { :name => "bytea" }, :boolean => { :name => "boolean" }, :xml => { :name => "xml" } }
Instance Attribute Summary
Attributes included from QueryCache
#query_cache, #query_cache_enabled
Instance Method Summary collapse
-
#active? ⇒ Boolean
Is this connection alive and ready for queries?.
-
#adapter_name ⇒ Object
Returns ‘PostgreSQL’ as adapter name for identification purposes.
-
#add_column(table_name, column_name, type, options = {}) ⇒ Object
Adds a new column to the named table.
-
#begin_db_transaction ⇒ Object
Begins a transaction.
-
#change_column(table_name, column_name, type, options = {}) ⇒ Object
Changes the column of a table.
-
#change_column_default(table_name, column_name, default) ⇒ Object
Changes the default value of a table column.
- #change_column_null(table_name, column_name, null, default = nil) ⇒ Object
-
#client_min_messages ⇒ Object
Returns the current client message level.
-
#client_min_messages=(level) ⇒ Object
Set the client message level.
-
#columns(table_name, name = nil) ⇒ Object
Returns the list of all column definitions for a table.
-
#commit_db_transaction ⇒ Object
Commits a transaction.
-
#create_database(name, options = {}) ⇒ Object
Create a new PostgreSQL database.
- #create_savepoint ⇒ Object
-
#current_database ⇒ Object
Returns the current database name.
-
#default_sequence_name(table_name, pk = nil) ⇒ Object
Returns the sequence name for a table’s primary key or some other specified key.
-
#disable_referential_integrity ⇒ Object
:nodoc:.
-
#disconnect! ⇒ Object
Close the connection.
-
#distinct(columns, order_by) ⇒ Object
Returns a SELECT DISTINCT clause for a given set of columns and a given ORDER BY clause.
-
#drop_database(name) ⇒ Object
Drops a PostgreSQL database.
-
#encoding ⇒ Object
Returns the current database encoding format.
-
#escape_bytea(value) ⇒ Object
Escapes binary strings for bytea input to the database.
-
#execute(sql, name = nil) ⇒ Object
Executes an SQL statement, returning a PGresult object on success or raising a PGError exception otherwise.
- #index_name_length ⇒ Object
-
#indexes(table_name, name = nil) ⇒ Object
Returns the list of all indexes for a table.
-
#initialize(connection, logger, connection_parameters, config) ⇒ PostgreSQLAdapter
constructor
Initializes and connects a PostgreSQL adapter.
-
#insert(sql, name = nil, pk = nil, id_value = nil, sequence_name = nil) ⇒ Object
(also: #create)
Executes an INSERT query and returns the new record’s ID.
-
#native_database_types ⇒ Object
:nodoc:.
- #outside_transaction? ⇒ Boolean
-
#pk_and_sequence_for(table) ⇒ Object
Returns a table’s primary key and belonging sequence.
-
#primary_key(table) ⇒ Object
Returns just a table’s primary key.
-
#query(sql, name = nil) ⇒ Object
Queries the database and returns the results in an Array-like object.
-
#quote(value, column = nil) ⇒ Object
Quotes PostgreSQL-specific data types for SQL input.
-
#quote_column_name(name) ⇒ Object
Quotes column names for use in SQL queries.
-
#quote_string(s) ⇒ Object
Quotes strings for use in SQL input.
-
#quote_table_name(name) ⇒ Object
Checks the following cases:.
-
#quoted_date(value) ⇒ Object
Quote date/time values for use in SQL input.
-
#reconnect! ⇒ Object
Close then reopen the connection.
-
#recreate_database(name) ⇒ Object
SCHEMA STATEMENTS ========================================.
- #release_savepoint ⇒ Object
-
#remove_index!(table_name, index_name) ⇒ Object
:nodoc:.
-
#rename_column(table_name, column_name, new_column_name) ⇒ Object
Renames a column in a table.
-
#rename_table(name, new_name) ⇒ Object
Renames a table.
-
#reset_pk_sequence!(table, pk = nil, sequence = nil) ⇒ Object
Resets the sequence of a table’s primary key to the maximum value.
-
#result_as_array(res) ⇒ Object
create a 2D array representing the result set.
-
#rollback_db_transaction ⇒ Object
Aborts a transaction.
- #rollback_to_savepoint ⇒ Object
-
#schema_search_path ⇒ Object
Returns the active schema search path.
-
#schema_search_path=(schema_csv) ⇒ Object
Sets the schema search path to a string of comma-separated schema names.
-
#select_rows(sql, name = nil) ⇒ Object
Executes a SELECT query and returns an array of rows.
-
#set_standard_conforming_strings ⇒ Object
Enable standard-conforming strings if available.
- #supports_ddl_transactions? ⇒ Boolean
-
#supports_disable_referential_integrity? ⇒ Boolean
REFERENTIAL INTEGRITY ====================================.
- #supports_insert_with_returning? ⇒ Boolean
-
#supports_migrations? ⇒ Boolean
Does PostgreSQL support migrations?.
-
#supports_primary_key? ⇒ Boolean
Does PostgreSQL support finding primary key on non-Active Record tables?.
- #supports_savepoints? ⇒ Boolean
-
#table_alias_length ⇒ Object
Returns the configured supported identifier length supported by PostgreSQL, or report the default of 63 on PostgreSQL 7.x.
- #table_exists?(name) ⇒ Boolean
-
#tables(name = nil) ⇒ Object
Returns the list of all tables in the schema search path or a specified schema.
-
#type_to_sql(type, limit = nil, precision = nil, scale = nil) ⇒ Object
Maps logical Rails types to PostgreSQL-specific data types.
-
#unescape_bytea(value) ⇒ Object
Unescapes bytea output from a database to the binary string it represents.
-
#update_sql(sql, name = nil) ⇒ Object
Executes an UPDATE query and returns the number of affected tuples.
Methods inherited from AbstractAdapter
#current_savepoint_name, #decrement_open_transactions, #increment_open_transactions, #open_transactions, #prefetch_primary_key?, #raw_connection, #requires_reloading?, #reset!, #supports_count_distinct?, #transaction_joinable=, #verify!
Methods included from QueryCache
#cache, #clear_query_cache, dirties_query_cache, included, #select_all, #uncached
Methods included from DatabaseLimits
#column_name_length, #columns_per_multicolumn_index, #columns_per_table, #in_clause_length, #indexes_per_table, #joins_per_query, #sql_query_length, #table_name_length
Methods included from Quoting
Methods included from DatabaseStatements
#add_limit_offset!, #add_transaction_record, #case_sensitive_equality_operator, #delete, #empty_insert_statement_value, #insert_fixture, #limited_update_conditions, #reset_sequence!, #select_all, #select_one, #select_value, #select_values, #transaction, #update
Methods included from SchemaStatements
#add_column_options!, #add_index, #add_timestamps, #assume_migrated_upto_version, #change_table, #column_exists?, #create_table, #drop_table, #dump_schema_information, #index_exists?, #index_name, #index_name_exists?, #initialize_schema_migrations_table, #remove_column, #remove_index, #remove_timestamps, #rename_index, #structure_dump, #table_alias_for
Constructor Details
#initialize(connection, logger, connection_parameters, config) ⇒ PostgreSQLAdapter
Initializes and connects a PostgreSQL adapter.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 219 def initialize(connection, logger, connection_parameters, config) super(connection, logger) @connection_parameters, @config = connection_parameters, config # @local_tz is initialized as nil to avoid warnings when connect tries to use it @local_tz = nil @table_alias_length = nil @postgresql_version = nil connect @local_tz = execute('SHOW TIME ZONE').first["TimeZone"] end |
Instance Method Details
#active? ⇒ Boolean
Is this connection alive and ready for queries?
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 233 def active? if @connection.respond_to?(:status) @connection.status == PGconn::CONNECTION_OK else # We're asking the driver, not Active Record, so use @connection.query instead of #query @connection.query 'SELECT 1' true end # postgres-pr raises a NoMethodError when querying if no connection is available. rescue PGError, NoMethodError false end |
#adapter_name ⇒ Object
Returns ‘PostgreSQL’ as adapter name for identification purposes.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 214 def adapter_name ADAPTER_NAME end |
#add_column(table_name, column_name, type, options = {}) ⇒ Object
Adds a new column to the named table. See TableDefinition#column for details of the options you can use.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 795 def add_column(table_name, column_name, type, = {}) default = [:default] notnull = [:null] == false # Add the column. execute("ALTER TABLE #{quote_table_name(table_name)} ADD COLUMN #{quote_column_name(column_name)} #{type_to_sql(type, [:limit], [:precision], [:scale])}") change_column_default(table_name, column_name, default) if () change_column_null(table_name, column_name, false, default) if notnull end |
#begin_db_transaction ⇒ Object
Begins a transaction.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 511 def begin_db_transaction execute "BEGIN" end |
#change_column(table_name, column_name, type, options = {}) ⇒ Object
Changes the column of a table.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 807 def change_column(table_name, column_name, type, = {}) quoted_table_name = quote_table_name(table_name) begin execute "ALTER TABLE #{quoted_table_name} ALTER COLUMN #{quote_column_name(column_name)} TYPE #{type_to_sql(type, [:limit], [:precision], [:scale])}" rescue ActiveRecord::StatementInvalid => e raise e if postgresql_version > 80000 # This is PostgreSQL 7.x, so we have to use a more arcane way of doing it. begin begin_db_transaction tmp_column_name = "#{column_name}_ar_tmp" add_column(table_name, tmp_column_name, type, ) execute "UPDATE #{quoted_table_name} SET #{quote_column_name(tmp_column_name)} = CAST(#{quote_column_name(column_name)} AS #{type_to_sql(type, [:limit], [:precision], [:scale])})" remove_column(table_name, column_name) rename_column(table_name, tmp_column_name, column_name) commit_db_transaction rescue rollback_db_transaction end end change_column_default(table_name, column_name, [:default]) if () change_column_null(table_name, column_name, [:null], [:default]) if .key?(:null) end |
#change_column_default(table_name, column_name, default) ⇒ Object
Changes the default value of a table column.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 833 def change_column_default(table_name, column_name, default) execute "ALTER TABLE #{quote_table_name(table_name)} ALTER COLUMN #{quote_column_name(column_name)} SET DEFAULT #{quote(default)}" end |
#change_column_null(table_name, column_name, null, default = nil) ⇒ Object
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 837 def change_column_null(table_name, column_name, null, default = nil) 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 execute("ALTER TABLE #{quote_table_name(table_name)} ALTER #{quote_column_name(column_name)} #{null ? 'DROP' : 'SET'} NOT NULL") end |
#client_min_messages ⇒ Object
Returns the current client message level.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 698 def query('SHOW client_min_messages')[0][0] end |
#client_min_messages=(level) ⇒ Object
Set the client message level.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 703 def (level) execute("SET client_min_messages TO '#{level}'") end |
#columns(table_name, name = nil) ⇒ Object
Returns the list of all column definitions for a table.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 660 def columns(table_name, name = nil) # Limit, precision, and scale are all handled by the superclass. column_definitions(table_name).collect do |name, type, default, notnull| PostgreSQLColumn.new(name, default, type, notnull == 'f') end end |
#commit_db_transaction ⇒ Object
Commits a transaction.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 516 def commit_db_transaction execute "COMMIT" end |
#create_database(name, options = {}) ⇒ Object
Create a new PostgreSQL database. Options include :owner
, :template
, :encoding
, :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'
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 555 def create_database(name, = {}) = .reverse_merge(:encoding => "utf8") option_string = .symbolize_keys.sum do |key, value| case key when :owner " OWNER = \"#{value}\"" when :template " TEMPLATE = \"#{value}\"" when :encoding " ENCODING = '#{value}'" when :tablespace " TABLESPACE = \"#{value}\"" when :connection_limit " CONNECTION LIMIT = #{value}" else "" end end execute "CREATE DATABASE #{quote_table_name(name)}#{option_string}" end |
#create_savepoint ⇒ Object
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 529 def create_savepoint execute("SAVEPOINT #{current_savepoint_name}") end |
#current_database ⇒ Object
Returns the current database name.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 668 def current_database query('select current_database()')[0][0] end |
#default_sequence_name(table_name, pk = nil) ⇒ Object
Returns the sequence name for a table’s primary key or some other specified key.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 708 def default_sequence_name(table_name, pk = nil) #:nodoc: default_pk, default_seq = pk_and_sequence_for(table_name) default_seq || "#{table_name}_#{pk || default_pk || 'id'}_seq" end |
#disable_referential_integrity ⇒ Object
:nodoc:
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 387 def disable_referential_integrity #:nodoc: if supports_disable_referential_integrity?() then execute(tables.collect { |name| "ALTER TABLE #{quote_table_name(name)} DISABLE TRIGGER ALL" }.join(";")) end yield ensure if supports_disable_referential_integrity?() then execute(tables.collect { |name| "ALTER TABLE #{quote_table_name(name)} ENABLE TRIGGER ALL" }.join(";")) end end |
#disconnect! ⇒ Object
Close the connection.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 258 def disconnect! @connection.close rescue nil end |
#distinct(columns, order_by) ⇒ Object
Returns a SELECT DISTINCT clause for a given set of columns and a given ORDER BY clause.
PostgreSQL requires the ORDER BY columns in the select list for distinct queries, and requires that the ORDER BY include the distinct column.
distinct("posts.id", "posts.created_at desc")
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 876 def distinct(columns, order_by) #:nodoc: return "DISTINCT #{columns}" if order_by.blank? # Construct a clean list of column names from the ORDER BY clause, removing # any ASC/DESC modifiers order_columns = order_by.split(',').collect { |s| s.split.first } order_columns.delete_if { |c| c.blank? } order_columns = order_columns.zip((0...order_columns.size).to_a).map { |s,i| "#{s} AS alias_#{i}" } # Return a DISTINCT ON() clause that's distinct on the columns we want but includes # all the required columns for the ORDER BY to work properly. sql = "DISTINCT ON (#{columns}) #{columns}, " sql << order_columns * ', ' end |
#drop_database(name) ⇒ Object
Drops a PostgreSQL database
Example:
drop_database 'matt_development'
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 582 def drop_database(name) #:nodoc: if postgresql_version >= 80200 execute "DROP DATABASE IF EXISTS #{quote_table_name(name)}" else begin execute "DROP DATABASE #{quote_table_name(name)}" rescue ActiveRecord::StatementInvalid @logger.warn "#{name} database doesn't exist." if @logger end end end |
#encoding ⇒ Object
Returns the current database encoding format.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 673 def encoding query(<<-end_sql)[0][0] SELECT pg_encoding_to_char(pg_database.encoding) FROM pg_database WHERE pg_database.datname LIKE '#{current_database}' end_sql end |
#escape_bytea(value) ⇒ Object
Escapes binary strings for bytea input to the database.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 305 def escape_bytea(value) @connection.escape_bytea(value) if value end |
#execute(sql, name = nil) ⇒ Object
Executes an SQL statement, returning a PGresult object on success or raising a PGError exception otherwise.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 495 def execute(sql, name = nil) log(sql, name) do if @async @connection.async_exec(sql) else @connection.exec(sql) end end end |
#index_name_length ⇒ Object
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 853 def index_name_length 63 end |
#indexes(table_name, name = nil) ⇒ Object
Returns the list of all indexes for a table.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 626 def indexes(table_name, name = nil) schemas = schema_search_path.split(/,/).map { |p| quote(p) }.join(',') result = query(<<-SQL, name) SELECT distinct i.relname, d.indisunique, d.indkey, t.oid FROM pg_class t, pg_class i, pg_index d WHERE i.relkind = 'i' AND d.indexrelid = i.oid AND d.indisprimary = 'f' AND t.oid = d.indrelid AND t.relname = '#{table_name}' AND i.relnamespace IN (SELECT oid FROM pg_namespace WHERE nspname IN (#{schemas}) ) ORDER BY i.relname SQL result.map do |row| index_name = row[0] unique = row[1] == 't' indkey = row[2].split(" ") oid = row[3] columns = Hash[query(<<-SQL, "Columns for index #{row[0]} on #{table_name}")] SELECT a.attnum, a.attname FROM pg_attribute a WHERE a.attrelid = #{oid} AND a.attnum IN (#{indkey.join(",")}) SQL column_names = columns.values_at(*indkey).compact column_names.empty? ? nil : IndexDefinition.new(table_name, index_name, unique, column_names) end.compact end |
#insert(sql, name = nil, pk = nil, id_value = nil, sequence_name = nil) ⇒ Object Also known as: create
Executes an INSERT query and returns the new record’s ID
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 407 def insert(sql, name = nil, pk = nil, id_value = nil, sequence_name = nil) # Extract the table from the insert sql. Yuck. table = sql.split(" ", 4)[2].gsub('"', '') # Try an insert with 'returning id' if available (PG >= 8.2) if supports_insert_with_returning? pk, sequence_name = *pk_and_sequence_for(table) unless pk if pk id = select_value("#{sql} RETURNING #{quote_column_name(pk)}") clear_query_cache return id end end # Otherwise, insert then grab last_insert_id. if insert_id = super insert_id else # If neither pk nor sequence name is given, look them up. unless pk || sequence_name pk, sequence_name = *pk_and_sequence_for(table) end # If a pk is given, fallback to default sequence name. # Don't fetch last insert id for a table without a pk. if pk && sequence_name ||= default_sequence_name(table, pk) last_insert_id(table, sequence_name) end end end |
#native_database_types ⇒ Object
:nodoc:
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 262 def native_database_types #:nodoc: NATIVE_DATABASE_TYPES end |
#outside_transaction? ⇒ Boolean
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 525 def outside_transaction? @connection.transaction_status == PGconn::PQTRANS_IDLE end |
#pk_and_sequence_for(table) ⇒ Object
Returns a table’s primary key and belonging sequence.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 734 def pk_and_sequence_for(table) #:nodoc: # First try looking for a sequence with a dependency on the # given table's primary key. result = query(<<-end_sql, 'PK and serial sequence')[0] SELECT attr.attname, seq.relname FROM pg_class seq, pg_attribute attr, pg_depend dep, pg_namespace name, pg_constraint cons WHERE seq.oid = dep.objid AND seq.relkind = 'S' AND attr.attrelid = dep.refobjid AND attr.attnum = dep.refobjsubid AND attr.attrelid = cons.conrelid AND attr.attnum = cons.conkey[1] AND cons.contype = 'p' AND dep.refobjid = '#{quote_table_name(table)}'::regclass end_sql if result.nil? or result.empty? # If that fails, try parsing the primary key's default value. # Support the 7.x and 8.0 nextval('foo'::text) as well as # the 8.1+ nextval('foo'::regclass). result = query(<<-end_sql, 'PK and custom sequence')[0] SELECT attr.attname, CASE WHEN split_part(def.adsrc, '''', 2) ~ '.' THEN substr(split_part(def.adsrc, '''', 2), strpos(split_part(def.adsrc, '''', 2), '.')+1) ELSE split_part(def.adsrc, '''', 2) END FROM pg_class t JOIN pg_attribute attr ON (t.oid = attrelid) JOIN pg_attrdef def ON (adrelid = attrelid AND adnum = attnum) JOIN pg_constraint cons ON (conrelid = adrelid AND adnum = conkey[1]) WHERE t.oid = '#{quote_table_name(table)}'::regclass AND cons.contype = 'p' AND def.adsrc ~* 'nextval' end_sql end # [primary_key, sequence] [result.first, result.last] rescue nil end |
#primary_key(table) ⇒ Object
Returns just a table’s primary key
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 783 def primary_key(table) pk_and_sequence = pk_and_sequence_for(table) pk_and_sequence && pk_and_sequence.first end |
#query(sql, name = nil) ⇒ Object
Queries the database and returns the results in an Array-like object
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 482 def query(sql, name = nil) #:nodoc: log(sql, name) do if @async res = @connection.async_exec(sql) else res = @connection.exec(sql) end return result_as_array(res) end end |
#quote(value, column = nil) ⇒ Object
Quotes PostgreSQL-specific data types for SQL input.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 317 def quote(value, column = nil) #:nodoc: return super unless column if value.kind_of?(String) && column.type == :binary "'#{escape_bytea(value)}'" elsif value.kind_of?(String) && column.sql_type == 'xml' "xml '#{quote_string(value)}'" elsif value.kind_of?(Numeric) && column.sql_type == 'money' # Not truly string input, so doesn't require (or allow) escape string syntax. "'#{value}'" elsif value.kind_of?(String) && column.sql_type =~ /^bit/ case value when /^[01]*$/ "B'#{value}'" # Bit-string notation when /^[0-9A-F]*$/i "X'#{value}'" # Hexadecimal notation end else super end end |
#quote_column_name(name) ⇒ Object
Quotes column names for use in SQL queries.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 364 def quote_column_name(name) #:nodoc: PGconn.quote_ident(name.to_s) end |
#quote_string(s) ⇒ Object
Quotes strings for use in SQL input.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 340 def quote_string(s) #:nodoc: @connection.escape(s) end |
#quote_table_name(name) ⇒ Object
Checks the following cases:
-
table_name
-
“table.name”
-
schema_name.table_name
-
schema_name.“table.name”
-
“schema.name”.table_name
-
“schema.name”.“table.name”
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 352 def quote_table_name(name) schema, name_part = extract_pg_identifier_from_name(name.to_s) unless name_part quote_column_name(schema) else table_name, name_part = extract_pg_identifier_from_name(name_part) "#{quote_column_name(schema)}.#{quote_column_name(table_name)}" end end |
#quoted_date(value) ⇒ Object
Quote date/time values for use in SQL input. Includes microseconds if the value is a Time responding to usec.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 370 def quoted_date(value) #:nodoc: if value.acts_like?(:time) && value.respond_to?(:usec) "#{super}.#{sprintf("%06d", value.usec)}" else super end end |
#reconnect! ⇒ Object
Close then reopen the connection.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 247 def reconnect! if @connection.respond_to?(:reset) @connection.reset configure_connection else disconnect! connect end end |
#recreate_database(name) ⇒ Object
SCHEMA STATEMENTS ========================================
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 543 def recreate_database(name) #:nodoc: drop_database(name) create_database(name) end |
#release_savepoint ⇒ Object
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 537 def release_savepoint execute("RELEASE SAVEPOINT #{current_savepoint_name}") end |
#remove_index!(table_name, index_name) ⇒ Object
:nodoc:
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 849 def remove_index!(table_name, index_name) #:nodoc: execute "DROP INDEX #{quote_table_name(index_name)}" end |
#rename_column(table_name, column_name, new_column_name) ⇒ Object
Renames a column in a table.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 845 def rename_column(table_name, column_name, new_column_name) execute "ALTER TABLE #{quote_table_name(table_name)} RENAME COLUMN #{quote_column_name(column_name)} TO #{quote_column_name(new_column_name)}" end |
#rename_table(name, new_name) ⇒ Object
Renames a table.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 789 def rename_table(name, new_name) execute "ALTER TABLE #{quote_table_name(name)} RENAME TO #{quote_table_name(new_name)}" end |
#reset_pk_sequence!(table, pk = nil, sequence = nil) ⇒ Object
Resets the sequence of a table’s primary key to the maximum value.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 714 def reset_pk_sequence!(table, pk = nil, sequence = nil) #:nodoc: unless pk and sequence default_pk, default_sequence = pk_and_sequence_for(table) pk ||= default_pk sequence ||= default_sequence end if pk if sequence quoted_sequence = quote_column_name(sequence) select_value <<-end_sql, 'Reset sequence' SELECT setval('#{quoted_sequence}', (SELECT COALESCE(MAX(#{quote_column_name pk})+(SELECT increment_by FROM #{quoted_sequence}), (SELECT min_value FROM #{quoted_sequence})) FROM #{quote_table_name(table)}), false) end_sql else @logger.warn "#{table} has primary key #{pk} with no default sequence" if @logger end end end |
#result_as_array(res) ⇒ Object
create a 2D array representing the result set
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 440 def result_as_array(res) #:nodoc: # check if we have any binary column and if they need escaping unescape_col = [] res.nfields.times do |j| unescape_col << res.ftype(j) end ary = [] res.ntuples.times do |i| ary << [] res.nfields.times do |j| data = res.getvalue(i,j) case unescape_col[j] # unescape string passed BYTEA field (OID == 17) when BYTEA_COLUMN_TYPE_OID data = unescape_bytea(data) if String === data # If this is a money type column and there are any currency symbols, # then strip them off. Indeed it would be prettier to do this in # PostgreSQLColumn.string_to_decimal but would break form input # fields that call value_before_type_cast. when MONEY_COLUMN_TYPE_OID # Because money output is formatted according to the locale, there are two # cases to consider (note the decimal separators): # (1) $12,345,678.12 # (2) $12.345.678,12 case data when /^-?\D+[\d,]+\.\d{2}$/ # (1) data.gsub!(/[^-\d\.]/, '') when /^-?\D+[\d\.]+,\d{2}$/ # (2) data.gsub!(/[^-\d,]/, '').sub!(/,/, '.') end end ary[i] << data end end return ary end |
#rollback_db_transaction ⇒ Object
Aborts a transaction.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 521 def rollback_db_transaction execute "ROLLBACK" end |
#rollback_to_savepoint ⇒ Object
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 533 def rollback_to_savepoint execute("ROLLBACK TO SAVEPOINT #{current_savepoint_name}") end |
#schema_search_path ⇒ Object
Returns the active schema search path.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 693 def schema_search_path @schema_search_path ||= query('SHOW search_path')[0][0] end |
#schema_search_path=(schema_csv) ⇒ Object
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.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 685 def schema_search_path=(schema_csv) if schema_csv execute "SET search_path TO #{schema_csv}" @schema_search_path = schema_csv end end |
#select_rows(sql, name = nil) ⇒ Object
Executes a SELECT query and returns an array of rows. Each row is an array of field values.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 402 def select_rows(sql, name = nil) select_raw(sql, name).last end |
#set_standard_conforming_strings ⇒ Object
Enable standard-conforming strings if available.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 277 def set_standard_conforming_strings old, self. = , 'panic' execute('SET standard_conforming_strings = on') rescue nil ensure self. = old end |
#supports_ddl_transactions? ⇒ Boolean
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 288 def supports_ddl_transactions? true end |
#supports_disable_referential_integrity? ⇒ Boolean
REFERENTIAL INTEGRITY ====================================
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 380 def supports_disable_referential_integrity?() #:nodoc: version = query("SHOW server_version")[0][0].split('.') version[0].to_i >= 8 && version[1].to_i >= 1 rescue return false end |
#supports_insert_with_returning? ⇒ Boolean
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 284 def supports_insert_with_returning? postgresql_version >= 80200 end |
#supports_migrations? ⇒ Boolean
Does PostgreSQL support migrations?
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 267 def supports_migrations? true end |
#supports_primary_key? ⇒ Boolean
Does PostgreSQL support finding primary key on non-Active Record tables?
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 272 def supports_primary_key? #:nodoc: true end |
#supports_savepoints? ⇒ Boolean
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 292 def supports_savepoints? true end |
#table_alias_length ⇒ Object
Returns the configured supported identifier length supported by PostgreSQL, or report the default of 63 on PostgreSQL 7.x.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 298 def table_alias_length @table_alias_length ||= (postgresql_version >= 80000 ? query('SHOW max_identifier_length')[0][0].to_i : 63) end |
#table_exists?(name) ⇒ Boolean
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 603 def table_exists?(name) name = name.to_s schema, table = name.split('.', 2) unless table # A table was provided without a schema table = schema schema = nil end if name =~ /^"/ # Handle quoted table names table = name schema = nil end query(<<-SQL).first[0].to_i > 0 SELECT COUNT(*) FROM pg_tables WHERE tablename = '#{table.gsub(/(^"|"$)/,'')}' #{schema ? "AND schemaname = '#{schema}'" : ''} SQL end |
#tables(name = nil) ⇒ Object
Returns the list of all tables in the schema search path or a specified schema.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 595 def tables(name = nil) query(<<-SQL, name).map { |row| row[0] } SELECT tablename FROM pg_tables WHERE schemaname = ANY (current_schemas(false)) SQL end |
#type_to_sql(type, limit = nil, precision = nil, scale = nil) ⇒ Object
Maps logical Rails types to PostgreSQL-specific data types.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 858 def type_to_sql(type, limit = nil, precision = nil, scale = nil) return super unless type.to_s == 'integer' return 'integer' unless limit case limit when 1, 2; 'smallint' when 3, 4; 'integer' when 5..8; 'bigint' else raise(ActiveRecordError, "No integer type has byte size #{limit}. Use a numeric with precision 0 instead.") end end |
#unescape_bytea(value) ⇒ Object
Unescapes bytea output from a database to the binary string it represents. NOTE: This is NOT an inverse of escape_bytea! This is only to be used
on escaped binary output from database drive.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 312 def unescape_bytea(value) @connection.unescape_bytea(value) if value end |
#update_sql(sql, name = nil) ⇒ Object
Executes an UPDATE query and returns the number of affected tuples.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 506 def update_sql(sql, name = nil) super.cmd_tuples end |