Thread: pgsql: Fix ADD IF NOT EXISTS used in conjunction with ALTER TABLE ONLY

Fix ADD IF NOT EXISTS used in conjunction with ALTER TABLE ONLY

The flag for IF NOT EXISTS was only being passed down in the normal
recursing case. It's been this way since originally added in 9.6 in
commit 2cd40adb85 so backpatch back to 9.6.

Branch
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REL_10_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/9e6cd794c282499aa0d2d31166c023cda0682e67

Modified Files
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src/backend/commands/tablecmds.c          | 2 +-
src/test/regress/expected/alter_table.out | 6 ++++++
src/test/regress/sql/alter_table.sql      | 4 ++++
3 files changed, 11 insertions(+), 1 deletion(-)