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NAME

       EXPLAIN -

SYNOPSIS

       EXPLAIN [ ANALYZE ] [ VERBOSE ] statement

DESCRIPTION

        PostgreSQL ---  ---

             EXISTS    LIMIT

       ANALYZE

              Important:
                  ANALYZE     EXPLAIN   SELECT     INSERTUPDATEDELETE  EXECUTE
              EXPLAIN ANALYZE

              BEGIN;
              EXPLAIN ANALYZE ...;
              ROLLBACK;

PARAMETERS

       ANALYZE

       VERBOSE
                PostgreSQL  VERBOSE   explain_pretty_print

       statement
                SELECT, INSERT, UPDATE, DELETE, EXECUTE,  DECLARE

NOTES

         PostgreSQL  Section 13.1 ``Using EXPLAIN''

         PostgreSQL   ANALYZE   ANALYZE

         PostgreSQL 7.3  NOTICE

EXAMPLES

         int4  10000

       EXPLAIN SELECT * FROM foo;

                              QUERY PLAN
       ---------------------------------------------------------
        Seq Scan on foo  (cost=0.00..155.00 rows=10000 width=4)
       (1 row)

         WHERE  EXPLAIN

       EXPLAIN SELECT * FROM foo WHERE i = 4;

                                QUERY PLAN
       --------------------------------------------------------------
        Index Scan using fi on foo  (cost=0.00..5.98 rows=1 width=4)
          Index Cond: (i = 4)
       (2 rows)

       EXPLAIN SELECT sum(i) FROM foo WHERE i < 10;

                                    QUERY PLAN
       ---------------------------------------------------------------------
        Aggregate  (cost=23.93..23.93 rows=1 width=4)
          ->  Index Scan using fi on foo  (cost=0.00..23.92 rows=6 width=4)
                Index Cond: (i < 10)
       (3 rows)

         EXPLAIN EXECUTE

       PREPARE query(int, int) AS SELECT sum(bar) FROM test
           WHERE id > $1 AND id < $2
           GROUP BY foo;

       EXPLAIN ANALYZE EXECUTE query(100, 200);

                                                              QUERY PLAN
       -------------------------------------------------------------------------------------------------------------------------
        HashAggregate  (cost=39.53..39.53 rows=1 width=8) (actual time=0.661..0.672 rows=7 loops=1)
          ->  Index Scan using test_pkey on test  (cost=0.00..32.97 rows=1311 width=8) (actual time=0.050..0.395 rows=99 loops=1)
                Index Cond: ((id > $1) AND (id < $2))
        Total runtime: 0.851 ms
       (4 rows)

          PostgreSQL-- ANALYZE   ANALYZE

COMPATIBILITY

         SQL EXPLAIN

       Postgresql  <laser@pgsqldb.org>