src/include/access/tupdesc_details.h

   1 /*-------------------------------------------------------------------------
   2  *
   3  * tupdesc_details.h
   4  *        POSTGRES tuple descriptor definitions we can't include everywhere
   5  *
   6  *
   7  * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
   8  * Portions Copyright (c) 1994, Regents of the University of California
   9  *
  10  * src/include/access/tupdesc_details.h
  11  *
  12  *-------------------------------------------------------------------------
  13  */
  14
  15 #ifndef TUPDESC_DETAILS_H
  16 #define TUPDESC_DETAILS_H
  17
  18 /*
  19  * Structure used to represent value to be used when the attribute is not
  20  * present at all in a tuple, i.e. when the column was created after the tuple
  21  */
  22 typedef struct AttrMissing
  23 {
  24         bool            am_present;             /* true if non-NULL missing value exists */
  25         Datum           am_value;               /* value when attribute is missing */
  26 } AttrMissing;
  27
  28 #endif                                                  /* TUPDESC_DETAILS_H */