database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-06-29 10:41:53 +03:00
Code Activity

Add notion of a "transform function" that can simplify function calls.

Browse Source 
Initially, we use this only to eliminate calls to the varchar()
function in cases where the length is not being reduced and, therefore,
the function call is equivalent to a RelabelType operation.  The most
significant effect of this is that we can avoid a table rewrite when
changing a varchar(X) column to a varchar(Y) column, where Y > X.

Noah Misch, reviewed by me and Alexey Klyukin
This commit is contained in:
Robert Haas
2011-06-21 22:15:24 -04:00
parent 771a9f69f7
commit 8f9fe6edce
11 changed files with 2401 additions and 2280 deletions
Download Patch File Download Diff File Expand all files Collapse all files

1
src/include/utils/builtins.h
View File

@ -684,6 +684,7 @@ extern Datum varcharrecv(PG_FUNCTION_ARGS);
extern Datum varcharsend(PG_FUNCTION_ARGS);
extern Datum varchartypmodin(PG_FUNCTION_ARGS);
extern Datum varchartypmodout(PG_FUNCTION_ARGS);
extern Datum varchar_transform(PG_FUNCTION_ARGS);
extern Datum varchar(PG_FUNCTION_ARGS);
/* varlena.c */