Changeset: 67dd2abd5927 for MonetDB
URL: http://dev.monetdb.org/hg/MonetDB?cmd=changeset;node=67dd2abd5927
Modified Files:
sql/src/test/BugTracker-2010/Tests/LIMIT_OFFSET_big-endian.Bug-2622.stable.out
Branch: Oct2010
Log Message:
approved new MAL plan
Most probably due to changes in the "canonical" SQL-2-MAL
translation, the plan for, e.g., some "SELECT ... ORDER BY ..."
queries has changed.
Though still producing the correct results, the new plans
might (at least in some special cases as given here) no
longer be considered "minimal", as the now use more MAL
statements to come to the same result.
TODO:
Develope ("peep-hole") MAL-optimizers that detect and
simplify canonically generated MAL code that --- for
good reasons of simplified canonical tranlation ---
appears to be "redundant" or "too verbose" or "not minimal"
(at least) in special cases.
diffs (56 lines):
diff -r 3a2062583451 -r 67dd2abd5927
sql/src/test/BugTracker-2010/Tests/LIMIT_OFFSET_big-endian.Bug-2622.stable.out
---
a/sql/src/test/BugTracker-2010/Tests/LIMIT_OFFSET_big-endian.Bug-2622.stable.out
Mon Oct 18 17:13:40 2010 +0200
+++
b/sql/src/test/BugTracker-2010/Tests/LIMIT_OFFSET_big-endian.Bug-2622.stable.out
Mon Oct 18 17:49:20 2010 +0200
@@ -303,10 +303,14 @@
_16 := bat.reverse(_15);
_17 := algebra.kdifference(_14,_16);
_18 := algebra.sortTail(_17);
- _19 := sql.resultSet(1,1,_18);
- sql.rsColumn(_19,"sys.oblo","a","int",32,0,_17);
- _24 := io.stdout();
- sql.exportResult(_24,_19);
+ _19 := calc.oid(0...@0);
+ _21 := algebra.markT(_18,_19);
+ _22 := bat.reverse(_21);
+ _23 := algebra.leftjoin(_22,_17);
+ _24 := sql.resultSet(1,1,_23);
+ sql.rsColumn(_24,"sys.oblo","a","int",32,0,_23);
+ _29 := io.stdout();
+ sql.exportResult(_29,_24);
end s6_1;
#EXPLAIN select * from oblo ORDER BY a OFFSET 2;
% .explain # table_name
@@ -325,18 +329,21 @@
_16 := bat.reverse(_15);
_17 := algebra.kdifference(_14,_16);
_18 := algebra.sortTail(_17);
- _19 := calc.wrd(2:wrd);
- _21 := calc.wrd(nil:wrd);
- _23 := calc.+(_19,_21);
- _24 := calc.-(_23,1);
- _25 := algebra.slice(_18,_19,_24);
- _26 := bat.mirror(_25);
- _27 := algebra.leftjoin(_26,_18);
- _28 := algebra.leftjoin(_26,_17);
- _29 := sql.resultSet(1,1,_27);
- sql.rsColumn(_29,"sys.oblo","a","int",32,0,_28);
- _34 := io.stdout();
- sql.exportResult(_34,_29);
+ _19 := calc.oid(0...@0);
+ _21 := algebra.markT(_18,_19);
+ _22 := bat.reverse(_21);
+ _23 := algebra.leftjoin(_22,_17);
+ _24 := calc.wrd(2:wrd);
+ _26 := calc.wrd(nil:wrd);
+ _28 := calc.+(_24,_26);
+ _29 := calc.-(_28,1);
+ _30 := algebra.slice(_23,_24,_29);
+ _31 := bat.mirror(_30);
+ _32 := algebra.leftjoin(_31,_23);
+ _33 := sql.resultSet(1,1,_32);
+ sql.rsColumn(_33,"sys.oblo","a","int",32,0,_32);
+ _38 := io.stdout();
+ sql.exportResult(_38,_33);
end s7_1;
#EXPLAIN select * from oblo ORDER BY a LIMIT 2;
% .explain # table_name
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