Module htup

Functions

HeapTupleGetRawCommandId^⚠

HeapTupleHeaderGetRawCommandId will give you what’s in the header whether it is useful or not. Most code should use HeapTupleHeaderGetCmin or HeapTupleHeaderGetCmax instead, but note that those Assert that you can get a legitimate result, ie you are in the originating transaction!

HeapTupleHeaderFrozen^⚠

Does the specified HeapTupleHeaderData represent a “frozen” tuple?

HeapTupleHeaderGetNatts^⚠

How many attributes does the specified HeapTupleHeader have?

HeapTupleHeaderGetRawXmin^⚠

HeapTupleHeaderGetRawXmin returns the “raw” xmin field, which is the xid originally used to insert the tuple. However, the tuple might actually be frozen (via HeapTupleHeaderSetXminFrozen) in which case the tuple’s xmin is visible to every snapshot. Prior to PostgreSQL 9.4, we actually changed the xmin to FrozenTransactionId, and that value may still be encountered on disk.

HeapTupleHeaderGetXmin^⚠

Returns the xmin value of the specified HeapTupleHeaderData

HeapTupleHeaderIsHeapOnly^⚠

Safety

HeapTupleHeaderIsHotUpdated^⚠

Safety

HeapTupleHeaderXminInvalid^⚠

Safety

HeapTupleNoNulls^⚠

Does the specified HeapTuple contain nulls?

heap_getattr^⚠

Extract an attribute of a heap tuple and return it as a Datum. This works for either system or user attributes. The given attnum is properly range-checked.