1
0
mirror of https://github.com/postgres/postgres.git synced 2025-06-17 17:02:08 +03:00

Generated columns

This is an SQL-standard feature that allows creating columns that are
computed from expressions rather than assigned, similar to a view or
materialized view but on a column basis.

This implements one kind of generated column: stored (computed on
write).  Another kind, virtual (computed on read), is planned for the
future, and some room is left for it.

Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Pavel Stehule <pavel.stehule@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/b151f851-4019-bdb1-699e-ebab07d2f40a@2ndquadrant.com
This commit is contained in:
Peter Eisentraut
2019-03-30 08:13:09 +01:00
parent 6b8b5364dd
commit fc22b6623b
84 changed files with 3067 additions and 157 deletions

View File

@ -520,6 +520,14 @@ check_agglevels_and_constraints(ParseState *pstate, Node *expr)
err = _("grouping operations are not allowed in partition key expressions");
break;
case EXPR_KIND_GENERATED_COLUMN:
if (isAgg)
err = _("aggregate functions are not allowed in column generation expressions");
else
err = _("grouping operations are not allowed in column generation expressions");
break;
case EXPR_KIND_CALL_ARGUMENT:
if (isAgg)
@ -922,6 +930,9 @@ transformWindowFuncCall(ParseState *pstate, WindowFunc *wfunc,
case EXPR_KIND_COPY_WHERE:
err = _("window functions are not allowed in COPY FROM WHERE conditions");
break;
case EXPR_KIND_GENERATED_COLUMN:
err = _("window functions are not allowed in column generation expressions");
break;
/*
* There is intentionally no default: case here, so that the