Allow ALTER TABLE .. SET NOT NULL to skip provably unnecessary scans. If existing CHECK or NOT NULL constraints preclude the presence of nulls, we need not look to see whether any are present.
Sergei Kornilov, reviewed by Stephen Frost, Ildar Musin, David Rowley, and by me. Discussion: http://postgr.es/m/[email protected] Branch ------ master Details ------- https://git.postgresql.org/pg/commitdiff/bbb96c3704c041d139181c6601e5bc770e045d26 Modified Files -------------- doc/src/sgml/ref/alter_table.sgml | 13 +++- src/backend/commands/tablecmds.c | 111 ++++++++++++++++++++++++------ src/test/regress/expected/alter_table.out | 54 +++++++++++++++ src/test/regress/sql/alter_table.sql | 40 +++++++++++ 4 files changed, 195 insertions(+), 23 deletions(-)
