Class: PG::BasicTypeMapForQueries

Inherits:
TypeMapByClass show all
Includes:
BasicTypeRegistry
Defined in:
lib/pg/basic_type_mapping.rb

Overview

Simple set of rules for type casting common Ruby types to PostgreSQL.

OIDs of supported type casts are not hard-coded in the sources, but are retrieved from the PostgreSQL’s pg_type table in PG::BasicTypeMapForQueries.new .

Query params are type casted based on the class of the given value.

Higher level libraries will most likely not make use of this class, but use their own derivation of PG::TypeMapByClass or another set of rules to choose suitable encoders and decoders for the values to be sent.

Example:

conn = PG::Connection.new
# Assign a default ruleset for type casts of input and output values.
conn.type_map_for_queries = PG::BasicTypeMapForQueries.new(conn)
# Execute a query. The Integer param value is typecasted internally by PG::BinaryEncoder::Int8.
# The format of the parameter is set to 1 (binary) and the OID of this parameter is set to 20 (int8).
res = conn.exec_params( "SELECT $1", [5] )

Instance Method Summary collapse

Methods inherited from TypeMapByClass

#[], #[]=, #coders

Methods included from TypeMap::DefaultTypeMappable

#default_type_map, #default_type_map=, #with_default_type_map

Constructor Details

#initialize(connection) ⇒ BasicTypeMapForQueries

Returns a new instance of BasicTypeMapForQueries.



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# File 'lib/pg/basic_type_mapping.rb', line 388

def initialize(connection)
	@coder_maps = build_coder_maps(connection)

	populate_encoder_list
	@array_encoders_by_klass = array_encoders_by_klass
	@anyarray_encoder = coder_by_name(0, :encoder, '_any')
end