The code was completing this pattern with a list of settable characters,
and it was possible to reach this state after completing a "ALTER
STATISTICS " with SET.
Author: Vignesh C
Discussion: https://postgr.es/m/CALDaNm2HHF_371o+EeSjxDDS17Cx7d-ko2h1fLU94=ob=4_ktg@mail.gmail.com
/* ALTER STATISTICS */
else if (Matches("ALTER", "STATISTICS", MatchAny))
COMPLETE_WITH("OWNER TO", "RENAME TO", "SET SCHEMA", "SET STATISTICS");
+ /* ALTER STATISTICS SET */
+ else if (Matches("ALTER", "STATISTICS", MatchAny, "SET"))
+ COMPLETE_WITH("SCHEMA", "STATISTICS");
/* ALTER TRIGGER , add ON */
else if (Matches("ALTER", "TRIGGER", MatchAny))