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.
Defined Under Namespace
Classes: StatementPool, TableDefinition
Constant Summary collapse
- ADAPTER_NAME =
'PostgreSQL'
- NATIVE_DATABASE_TYPES =
{ :primary_key => "serial primary key", :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" }, :tsvector => { :name => "tsvector" } }
Instance Attribute Summary
Attributes inherited from AbstractAdapter
Attributes included from QueryCache
#query_cache, #query_cache_enabled
Class Method Summary collapse
-
.visitor_for(pool) ⇒ Object
:nodoc:.
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
-
#clear_cache! ⇒ Object
Clears the prepared statements cache.
-
#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
Disconnects from the database if already connected.
-
#distinct(columns, orders) ⇒ 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.
- #exec_delete(sql, name = 'SQL', binds = []) ⇒ Object (also: #exec_update)
- #exec_query(sql, name = 'SQL', binds = []) ⇒ Object
-
#execute(sql, name = nil) ⇒ Object
Executes an SQL statement, returning a PGresult object on success or raising a PGError exception otherwise.
-
#extract_schema_and_table(name) ⇒ Object
Extracts the table and schema name from
name
. - #index_name_length ⇒ Object
-
#indexes(table_name, name = nil) ⇒ Object
Returns an array of indexes for the given table.
-
#initialize(connection, logger, connection_parameters, config) ⇒ PostgreSQLAdapter
constructor
Initializes and connects a PostgreSQL adapter.
-
#insert_sql(sql, name = nil, pk = nil, id_value = nil, sequence_name = nil) ⇒ Object
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_index(table_name, old_name, new_name) ⇒ Object
-
#rename_table(name, new_name) ⇒ Object
Renames a table.
- #reset! ⇒ Object
-
#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.
- #serial_sequence(table, column) ⇒ Object
-
#session_auth=(user) ⇒ Object
Set the authorized user for this session.
-
#set_standard_conforming_strings ⇒ Object
Enable standard-conforming strings if available.
- #sql_for_insert(sql, pk, id_value, sequence_name, binds) ⇒ Object
- #substitute_at(column, index) ⇒ Object
- #supports_ddl_transactions? ⇒ Boolean
-
#supports_disable_referential_integrity? ⇒ Boolean
REFERENTIAL INTEGRITY ====================================.
- #supports_insert_with_returning? ⇒ Boolean
-
#supports_migrations? ⇒ Boolean
Returns true, since this connection adapter supports migrations.
-
#supports_primary_key? ⇒ Boolean
Does PostgreSQL support finding primary key on non-Active Record tables?.
-
#supports_savepoints? ⇒ Boolean
Returns true, since this connection adapter supports savepoints.
-
#supports_statement_cache? ⇒ Boolean
Returns
true
, since this connection adapter supports prepared statement caching. -
#table_alias_length ⇒ Object
Returns the configured supported identifier length supported by PostgreSQL.
- #table_exists?(name) ⇒ Boolean
-
#tables(name = nil) ⇒ Object
Returns the list of all tables in the schema search path or a specified schema.
- #type_cast(value, column) ⇒ Object
-
#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
#case_sensitive_modifier, #current_savepoint_name, #decrement_open_transactions, #increment_open_transactions, #open_transactions, #prefetch_primary_key?, #raw_connection, #requires_reloading?, #supports_bulk_alter?, #supports_count_distinct?, #transaction_joinable=, #verify!
Methods included from QueryCache
#cache, #clear_query_cache, dirties_query_cache, #disable_query_cache!, #enable_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, #exec_insert, #insert, #insert_fixture, #join_to_update, #limited_update_conditions, #reset_sequence!, #sanitize_limit, #select_all, #select_one, #select_value, #select_values, #to_sql, #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, #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 304 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 connect @statements = StatementPool.new @connection, config.fetch(:statement_limit) { 1000 } if postgresql_version < 80200 raise "Your version of PostgreSQL (#{postgresql_version}) is too old, please upgrade!" end @local_tz = execute('SHOW TIME ZONE', 'SCHEMA').first["TimeZone"] end |
Class Method Details
.visitor_for(pool) ⇒ Object
:nodoc:
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 323 def self.visitor_for(pool) # :nodoc: Arel::Visitors::PostgreSQL.new(pool) 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 333 def active? @connection.status == PGconn::CONNECTION_OK rescue PGError 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 241 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 918 def add_column(table_name, column_name, type, = {}) clear_cache! add_column_sql = "ALTER TABLE #{quote_table_name(table_name)} ADD COLUMN #{quote_column_name(column_name)} #{type_to_sql(type, [:limit], [:precision], [:scale])}" (add_column_sql, ) execute add_column_sql end |
#begin_db_transaction ⇒ Object
Begins a transaction.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 640 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 927 def change_column(table_name, column_name, type, = {}) clear_cache! quoted_table_name = quote_table_name(table_name) execute "ALTER TABLE #{quoted_table_name} ALTER COLUMN #{quote_column_name(column_name)} TYPE #{type_to_sql(type, [:limit], [:precision], [:scale])}" 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 938 def change_column_default(table_name, column_name, default) clear_cache! 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 943 def change_column_null(table_name, column_name, null, default = nil) clear_cache! 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 |
#clear_cache! ⇒ Object
Clears the prepared statements cache.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 328 def clear_cache! @statements.clear 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 827 def query('SHOW client_min_messages', 'SCHEMA')[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 832 def (level) execute("SET client_min_messages TO '#{level}'", 'SCHEMA') 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 789 def columns(table_name, name = nil) # Limit, precision, and scale are all handled by the superclass. column_definitions(table_name).collect do |column_name, type, default, notnull| PostgreSQLColumn.new(column_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 645 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 684 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 658 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 797 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 837 def default_sequence_name(table_name, pk = nil) #:nodoc: serial_sequence(table_name, pk || 'id').split('.').last rescue ActiveRecord::StatementInvalid "#{table_name}_#{pk || 'id'}_seq" end |
#disable_referential_integrity ⇒ Object
:nodoc:
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 504 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
Disconnects from the database if already connected. Otherwise, this method does nothing.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 353 def disconnect! clear_cache! @connection.close rescue nil end |
#distinct(columns, orders) ⇒ 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 988 def distinct(columns, orders) #:nodoc: return "DISTINCT #{columns}" if orders.empty? # Construct a clean list of column names from the ORDER BY clause, removing # any ASC/DESC modifiers order_columns = orders.collect { |s| s.gsub(/\s+(ASC|DESC)\s*/i, '') } 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}" } "DISTINCT #{columns}, #{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 711 def drop_database(name) #:nodoc: execute "DROP DATABASE IF EXISTS #{quote_table_name(name)}" end |
#encoding ⇒ Object
Returns the current database encoding format.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 802 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 401 def escape_bytea(value) @connection.escape_bytea(value) if value end |
#exec_delete(sql, name = 'SQL', binds = []) ⇒ Object Also known as: exec_update
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 611 def exec_delete(sql, name = 'SQL', binds = []) log(sql, name, binds) do result = binds.empty? ? exec_no_cache(sql, binds) : exec_cache(sql, binds) affected = result.cmd_tuples result.clear affected end end |
#exec_query(sql, name = 'SQL', binds = []) ⇒ Object
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 600 def exec_query(sql, name = 'SQL', binds = []) log(sql, name, binds) do result = binds.empty? ? exec_no_cache(sql, binds) : exec_cache(sql, binds) ret = ActiveRecord::Result.new(result.fields, result_as_array(result)) result.clear return ret end 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 590 def execute(sql, name = nil) log(sql, name) do @connection.async_exec(sql) end end |
#extract_schema_and_table(name) ⇒ Object
Extracts the table and schema name from name
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 740 def extract_schema_and_table(name) 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 [schema, table] end |
#index_name_length ⇒ Object
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 965 def index_name_length 63 end |
#indexes(table_name, name = nil) ⇒ Object
Returns an array of indexes for the given table.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 756 def indexes(table_name, name = nil) result = query(<<-SQL, name) SELECT distinct i.relname, d.indisunique, d.indkey, t.oid FROM pg_class t INNER JOIN pg_index d ON t.oid = d.indrelid INNER JOIN pg_class i ON d.indexrelid = i.oid WHERE i.relkind = 'i' AND d.indisprimary = 'f' AND t.relname = '#{table_name}' AND i.relnamespace IN (SELECT oid FROM pg_namespace WHERE nspname = ANY (current_schemas(false)) ) 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(sql, name = nil, pk = nil, id_value = nil, sequence_name = nil) ⇒ Object
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 524 def insert_sql(sql, name = nil, pk = nil, id_value = nil, sequence_name = nil) # Extract the table from the insert sql. Yuck. _, table = extract_schema_and_table(sql.split(" ", 4)[2]) pk ||= primary_key(table) if pk select_value("#{sql} RETURNING #{quote_column_name(pk)}") else super end end |
#native_database_types ⇒ Object
:nodoc:
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 358 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 654 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 873 def pk_and_sequence_for(table) #:nodoc: # First try looking for a sequence with a dependency on the # given table's primary key. result = exec_query(<<-end_sql, 'SCHEMA').rows.first SELECT attr.attname, seq.relname FROM pg_class seq INNER JOIN pg_depend dep ON seq.oid = dep.objid INNER JOIN pg_attribute attr ON attr.attrelid = dep.refobjid AND attr.attnum = dep.refobjsubid INNER JOIN pg_constraint cons ON attr.attrelid = cons.conrelid AND attr.attnum = cons.conkey[1] WHERE seq.relkind = 'S' AND cons.contype = 'p' AND dep.refobjid = '#{quote_table_name(table)}'::regclass end_sql # [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 894 def primary_key(table) row = exec_query(<<-end_sql, 'SCHEMA', [[nil, table]]).rows.first SELECT DISTINCT(attr.attname) FROM pg_attribute attr INNER JOIN pg_depend dep ON attr.attrelid = dep.refobjid AND attr.attnum = dep.refobjsubid INNER JOIN pg_constraint cons ON attr.attrelid = cons.conrelid AND attr.attnum = cons.conkey[1] WHERE cons.contype = 'p' AND dep.refobjid = $1::regclass end_sql row && row.first end |
#query(sql, name = nil) ⇒ Object
Queries the database and returns the results in an Array-like object
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 582 def query(sql, name = nil) #:nodoc: log(sql, name) do result_as_array @connection.async_exec(sql) end end |
#quote(value, column = nil) ⇒ Object
Quotes PostgreSQL-specific data types for SQL input.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 413 def quote(value, column = nil) #:nodoc: return super unless column case value when Float return super unless value.infinite? && column.type == :datetime "'#{value.to_s.downcase}'" when Numeric return super unless column.sql_type == 'money' # Not truly string input, so doesn't require (or allow) escape string syntax. "'#{value}'" when String case column.sql_type when 'bytea' then "'#{escape_bytea(value)}'" when 'xml' then "xml '#{quote_string(value)}'" when /^bit/ case value when /^[01]*$/ then "B'#{value}'" # Bit-string notation when /^[0-9A-F]*$/i then "X'#{value}'" # Hexadecimal notation end else super 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 478 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 454 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 466 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 484 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 340 def reconnect! clear_cache! @connection.reset configure_connection end |
#recreate_database(name) ⇒ Object
SCHEMA STATEMENTS ========================================
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 672 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 666 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 957 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 952 def rename_column(table_name, column_name, new_column_name) clear_cache! execute "ALTER TABLE #{quote_table_name(table_name)} RENAME COLUMN #{quote_column_name(column_name)} TO #{quote_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/postgresql_adapter.rb', line 961 def rename_index(table_name, old_name, new_name) execute "ALTER INDEX #{quote_column_name(old_name)} RENAME TO #{quote_table_name(new_name)}" end |
#rename_table(name, new_name) ⇒ Object
Renames a table.
Example:
rename_table('octopuses', 'octopi')
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 911 def rename_table(name, new_name) clear_cache! execute "ALTER TABLE #{quote_table_name(name)} RENAME TO #{quote_table_name(new_name)}" end |
#reset! ⇒ Object
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 346 def reset! clear_cache! super 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 851 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 @logger && pk && !sequence @logger.warn "#{table} has primary key #{pk} with no default sequence" end if pk && 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 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 539 def result_as_array(res) #:nodoc: # check if we have any binary column and if they need escaping ftypes = Array.new(res.nfields) do |i| [i, res.ftype(i)] end rows = res.values return rows unless ftypes.any? { |_, x| x == BYTEA_COLUMN_TYPE_OID || x == MONEY_COLUMN_TYPE_OID } typehash = ftypes.group_by { |_, type| type } binaries = typehash[BYTEA_COLUMN_TYPE_OID] || [] monies = typehash[MONEY_COLUMN_TYPE_OID] || [] rows.each do |row| # unescape string passed BYTEA field (OID == 17) binaries.each do |index, _| row[index] = unescape_bytea(row[index]) end # 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. monies.each do |index, _| data = row[index] # 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 end end |
#rollback_db_transaction ⇒ Object
Aborts a transaction.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 650 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 662 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 822 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 814 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 519 def select_rows(sql, name = nil) select_raw(sql, name).last end |
#serial_sequence(table, column) ⇒ Object
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 843 def serial_sequence(table, column) result = exec_query(<<-eosql, 'SCHEMA', [[nil, table], [nil, column]]) SELECT pg_get_serial_sequence($1, $2) eosql result.rows.first.first end |
#session_auth=(user) ⇒ Object
Set the authorized user for this session
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 493 def session_auth=(user) clear_cache! exec_query "SET SESSION AUTHORIZATION #{user}" end |
#set_standard_conforming_strings ⇒ Object
Enable standard-conforming strings if available.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 373 def set_standard_conforming_strings old, self. = , 'panic' execute('SET standard_conforming_strings = on', 'SCHEMA') rescue nil ensure self. = old end |
#sql_for_insert(sql, pk, id_value, sequence_name, binds) ⇒ Object
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 622 def sql_for_insert(sql, pk, id_value, sequence_name, binds) unless pk _, table = extract_schema_and_table(sql.split(" ", 4)[2]) pk = primary_key(table) end sql = "#{sql} RETURNING #{quote_column_name(pk)}" if pk [sql, binds] end |
#substitute_at(column, index) ⇒ Object
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 596 def substitute_at(column, index) Arel.sql("$#{index + 1}") end |
#supports_ddl_transactions? ⇒ Boolean
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 384 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 500 def supports_disable_referential_integrity? #:nodoc: true end |
#supports_insert_with_returning? ⇒ Boolean
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 380 def supports_insert_with_returning? true end |
#supports_migrations? ⇒ Boolean
Returns true, since this connection adapter supports migrations.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 363 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 368 def supports_primary_key? #:nodoc: true end |
#supports_savepoints? ⇒ Boolean
Returns true, since this connection adapter supports savepoints.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 389 def supports_savepoints? true end |
#supports_statement_cache? ⇒ Boolean
Returns true
, since this connection adapter supports prepared statement caching.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 247 def supports_statement_cache? true end |
#table_alias_length ⇒ Object
Returns the configured supported identifier length supported by PostgreSQL
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 394 def table_alias_length @table_alias_length ||= query('SHOW max_identifier_length')[0][0].to_i end |
#table_exists?(name) ⇒ Boolean
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 724 def table_exists?(name) schema, table = extract_schema_and_table(name.to_s) return false unless table # Abstract classes is having nil table name binds = [[nil, table.gsub(/(^"|"$)/,'')]] binds << [nil, schema] if schema exec_query(<<-SQL, 'SCHEMA', binds).rows.first[0].to_i > 0 SELECT COUNT(*) FROM pg_tables WHERE tablename = $1 AND schemaname = #{schema ? "$2" : "ANY (current_schemas(false))"} 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 716 def tables(name = nil) query(<<-SQL, 'SCHEMA').map { |row| row[0] } SELECT tablename FROM pg_tables WHERE schemaname = ANY (current_schemas(false)) SQL end |
#type_cast(value, column) ⇒ Object
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 441 def type_cast(value, column) return super unless column case value when String return super unless 'bytea' == column.sql_type { :value => value, :format => 1 } else super end 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 970 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 408 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 635 def update_sql(sql, name = nil) super.cmd_tuples end |