I’ve installed phpPgAdmin to try to reproduce your error. I got it right away when tried to create a test table:
So looks like phpPgAdmin wraping your query into select count(*) as total from (...)
. I’ve found that it happens only when checkbox “Paginate results” on query page is set to on (obviously phpPgAdmin trying to count how many rows it will get and then show it page by page). Uncheck it and your query will work fine:
updated 1
Similar question – INSERT INTO PostgreSQL
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As @akshay mentioned in comments, you also could get similar error running the queries through the command line, see explained situation and answer here – PostgreSQL disable more output