pg_select dbHandle queryString arrayVar queryProcedure
Specifies a valid database handle.
Specifies a valid SQL select query.
Array variable for tuples returned.
Procedure run on each tuple found.
the return result is either an error message or a handle for a query result.
pg_select submits a SELECT query to the Postgres backend, and executes a given chunk of code for each tuple in the result. The queryString must be a SELECT statement. Anything else returns an error. The arrayVar variable is an array name used in the loop. For each tuple, arrayVar is filled in with the tuple field values, using the field names as the array indexes. Then the queryProcedure is executed.
This would work if table "table" has fields "control" and "name" (and, perhaps, other fields):
pg_select $pgconn "SELECT * from table" array {
puts [format "%5d %s" array(control) array(name)]
}