Thread: proposal: allow to specify result tupdesc and mode in SPI API

proposal: allow to specify result tupdesc and mode in SPI API

From

Pavel Stehule

Date:

14 August 2014, 07:30:06

Hello

we have not possibility to simple specify result types in SPI API functions. Planner has this functionality - see transformInsertRow function, but it is not visible from SPI.

A new function should to look like:

SPIPlanPtr
SPI_prepare_params_rettupdesc(const char *src,
                                   ParserSetupHook parserSetup,
                                   void *parserSetupArg,
                                   int cursorOptions,

TupDesc *retTupDesc,

int CoercionMode)

CoercionMode should be:

COERCION_MODE_SQL .. same as INSERT or UPDATE does

COERCION_MODE_SQL_NOERROR .. same as above with possible IO cast

COERCION_MODE_EXPLICIT .. same as using explicit casting

COERCION_MODE_EXPLICIT_NOERROR .. same as previous with possible IO cast

Benefits:

* simplify life to SPI users - no necessary late casting

* possible small simplification of plpgsql with two benefits:

** reduce performance impact of hidden IO cast

** reduce possible issues with type transformation via hidden IO cast

Comments, notes?

Regards

Pavel Stehule