diff options
| author | Tom Lane <tgl@sss.pgh.pa.us> | 2002-03-24 17:11:37 +0000 | 
|---|---|---|
| committer | Tom Lane <tgl@sss.pgh.pa.us> | 2002-03-24 17:11:37 +0000 | 
| commit | ea10ec1b69c0aba24c1dc4570f40e976a42bfddb (patch) | |
| tree | bafed68bf8ad65b9d71cc5530ac5d328480a74d0 /doc/src/sgml | |
| parent | 7100cbc1c42f4a20ef14721336b6857b4b489f2f (diff) | |
Tweak labeling of plan qual conditions for more consistency.
Diffstat (limited to 'doc/src/sgml')
| -rw-r--r-- | doc/src/sgml/perform.sgml | 24 | ||||
| -rw-r--r-- | doc/src/sgml/ref/explain.sgml | 6 | 
2 files changed, 15 insertions, 15 deletions
diff --git a/doc/src/sgml/perform.sgml b/doc/src/sgml/perform.sgml index 6b13d6ae3af..17c8a348d0f 100644 --- a/doc/src/sgml/perform.sgml +++ b/doc/src/sgml/perform.sgml @@ -1,5 +1,5 @@  <!-- -$Header: /cvsroot/pgsql/doc/src/sgml/perform.sgml,v 1.19 2002/03/24 04:31:05 tgl Exp $ +$Header: /cvsroot/pgsql/doc/src/sgml/perform.sgml,v 1.20 2002/03/24 17:11:37 tgl Exp $  -->   <chapter id="performance-tips"> @@ -116,7 +116,7 @@ SELECT * FROM pg_class WHERE relname = 'tenk1';     </para>     <para> -    Now let's modify the query to add a qualification clause: +    Now let's modify the query to add a WHERE condition:      <programlisting>  regression=# EXPLAIN SELECT * FROM tenk1 WHERE unique1 < 1000; @@ -142,14 +142,14 @@ regression=# EXPLAIN SELECT * FROM tenk1 WHERE unique1 < 1000;     </para>     <para> -    Modify the query to restrict the qualification even more: +    Modify the query to restrict the condition even more:      <programlisting>  regression=# EXPLAIN SELECT * FROM tenk1 WHERE unique1 < 50;                                     QUERY PLAN  -------------------------------------------------------------------------------   Index Scan using tenk1_unique1 on tenk1  (cost=0.00..179.33 rows=49 width=148) -   Index Filter: (unique1 < 50) +   Index Cond: (unique1 < 50)      </programlisting>      and you will see that if we make the WHERE condition selective @@ -161,7 +161,7 @@ regression=# EXPLAIN SELECT * FROM tenk1 WHERE unique1 < 50;     </para>     <para> -    Add another condition to the qualification: +    Add another clause to the WHERE condition:      <programlisting>  regression=# EXPLAIN SELECT * FROM tenk1 WHERE unique1 < 50 AND @@ -169,7 +169,7 @@ regression-# stringu1 = 'xxx';                                    QUERY PLAN  -------------------------------------------------------------------------------   Index Scan using tenk1_unique1 on tenk1  (cost=0.00..179.45 rows=1 width=148) -   Index Filter: (unique1 < 50) +   Index Cond: (unique1 < 50)     Filter: (stringu1 = 'xxx'::name)      </programlisting> @@ -193,10 +193,10 @@ regression-# AND t1.unique2 = t2.unique2;   Nested Loop  (cost=0.00..327.02 rows=49 width=296)     ->  Index Scan using tenk1_unique1 on tenk1 t1                                        (cost=0.00..179.33 rows=49 width=148) -         Index Filter: (unique1 < 50) +         Index Cond: (unique1 < 50)     ->  Index Scan using tenk2_unique2 on tenk2 t2                                        (cost=0.00..3.01 rows=1 width=148) -         Index Filter: ("outer".unique2 = t2.unique2) +         Index Cond: ("outer".unique2 = t2.unique2)      </programlisting>     </para> @@ -208,7 +208,7 @@ regression-# AND t1.unique2 = t2.unique2;      affect row count of the outer scan.  For the inner scan, the unique2 value of the      current      outer-scan tuple is plugged into the inner index scan -    to produce an index qualification like +    to produce an index condition like      <literal>t2.unique2 = <replaceable>constant</replaceable></literal>.  So we get the       same inner-scan plan and costs that we'd get from, say, <literal>explain select       * from tenk2 where unique2 = 42</literal>.  The costs of the loop node are then set @@ -246,7 +246,7 @@ regression-# AND t1.unique2 = t2.unique2;     ->  Hash  (cost=179.33..179.33 rows=49 width=148)           ->  Index Scan using tenk1_unique1 on tenk1 t1                                      (cost=0.00..179.33 rows=49 width=148) -               Index Filter: (unique1 < 50) +               Index Cond: (unique1 < 50)      </programlisting>      This plan proposes to extract the 50 interesting rows of <classname>tenk1</classname> @@ -279,11 +279,11 @@ regression-# WHERE t1.unique1 < 50 AND t1.unique2 = t2.unique2;     ->  Index Scan using tenk1_unique1 on tenk1 t1                    (cost=0.00..179.33 rows=49 width=148)                                   (actual time=0.63..8.91 rows=50 loops=1) -         Index Filter: (unique1 < 50) +         Index Cond: (unique1 < 50)     ->  Index Scan using tenk2_unique2 on tenk2 t2                    (cost=0.00..3.01 rows=1 width=148)                                   (actual time=0.29..0.32 rows=1 loops=50) -         Index Filter: ("outer".unique2 = t2.unique2) +         Index Cond: ("outer".unique2 = t2.unique2)   Total runtime: 31.60 msec  </screen> diff --git a/doc/src/sgml/ref/explain.sgml b/doc/src/sgml/ref/explain.sgml index e8ef9fc76f4..46c6c8c955b 100644 --- a/doc/src/sgml/ref/explain.sgml +++ b/doc/src/sgml/ref/explain.sgml @@ -1,5 +1,5 @@  <!-- -$Header: /cvsroot/pgsql/doc/src/sgml/ref/explain.sgml,v 1.18 2002/03/24 16:57:29 tgl Exp $ +$Header: /cvsroot/pgsql/doc/src/sgml/ref/explain.sgml,v 1.19 2002/03/24 17:11:37 tgl Exp $  PostgreSQL documentation  --> @@ -209,7 +209,7 @@ 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 Filter: (i = 4) +   Index Cond: (i = 4)  (2 rows)      </computeroutput>     </programlisting> @@ -226,7 +226,7 @@ EXPLAIN SELECT sum(i) FROM foo WHERE i < 10;  ---------------------------------------------------------------------   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 Filter: (i < 10) +         Index Cond: (i < 10)  (3 rows)      </computeroutput>     </programlisting>  | 
