pgsql: doc: Fix column_name parameter in ALTER MATERIALIZED VIEW

doc: Fix column_name parameter in ALTER MATERIALIZED VIEW

Parameter column_name must be an existing column because ALTER
MATERIALIZED VIEW cannot add new columns. The old description was
likely copied from ALTER TABLE.

Author: Erik Wienhold
Discussion: /messages/by-id/6880ca53-7961-4eeb-86d5-6bd05fc2027e@ewie.name
Backpatch-through: 12

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/dd087e1c13bf5f2bcfdc189976aa4e44ed431739

Modified Files
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doc/src/sgml/ref/alter_materialized_view.sgml | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)