]> granicus.if.org Git - postgresql/blob - src/include/access/tupdesc_details.h
Fast ALTER TABLE ADD COLUMN with a non-NULL default
[postgresql] / 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) 1996-2018, 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
23 typedef struct attrMissing
24 {
25         bool            ammissingPresent;       /* true if non-NULL missing value exists */
26         Datum           ammissing;              /* value when attribute is missing */
27 } AttrMissing;
28
29 #endif                                                  /* TUPDESC_DETAILS_H */