wasCSharpSQLite – Blame information for rev 7
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1 | office | 1 | # 2009 March 28 |
2 | # |
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3 | # The author disclaims copyright to this source code. In place of |
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4 | # a legal notice, here is a blessing: |
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5 | # |
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6 | # May you do good and not evil. |
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7 | # May you find forgiveness for yourself and forgive others. |
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8 | # May you share freely, never taking more than you give. |
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9 | # |
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10 | #*********************************************************************** |
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11 | # |
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12 | # Ticket #3757: The cost functions on the query optimizer for the |
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13 | # IN operator can be improved. |
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14 | # |
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15 | # $Id: tkt3757.test,v 1.1 2009/03/29 00:13:04 drh Exp $ |
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16 | |||
17 | set testdir [file dirname $argv0] |
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18 | source $testdir/tester.tcl |
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19 | |||
20 | # Evaluate SQL. Return the result set followed by the |
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21 | # and the number of full-scan steps. |
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22 | # |
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23 | proc count_steps {sql} { |
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24 | set r [db eval $sql] |
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25 | lappend r scan [db status step] sort [db status sort] |
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26 | } |
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27 | |||
28 | # Construct tables |
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29 | # |
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30 | do_test tkt3757-1.1 { |
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31 | db eval { |
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32 | CREATE TABLE t1(x INTEGER, y INTEGER, z TEXT); |
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33 | CREATE INDEX t1i1 ON t1(y,z); |
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34 | INSERT INTO t1 VALUES(1,2,'three'); |
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35 | CREATE TABLE t2(a INTEGER, b TEXT); |
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36 | INSERT INTO t2 VALUES(2, 'two'); |
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37 | ANALYZE; |
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38 | SELECT * FROM sqlite_stat1 ORDER BY 1, 2; |
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39 | } |
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40 | } {t1 t1i1 {1 1 1} t2 {} 1} |
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41 | |||
42 | # Modify statistics in order to make the optimizer then that: |
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43 | # |
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44 | # (1) Table T1 has about 250K entries |
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45 | # (2) There are only about 5 distinct values of T1. |
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46 | # |
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47 | # Then run a query with "t1.y IN (SELECT ..)" in the WHERE clause. |
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48 | # Make sure the index is used. |
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49 | # |
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50 | do_test tkt3757-1.2 { |
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51 | db eval { |
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52 | DELETE FROM sqlite_stat1; |
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53 | INSERT INTO sqlite_stat1 VALUES('t1','t1i1','250000 50000 30'); |
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54 | } |
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55 | count_steps { |
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56 | SELECT * FROM t1 WHERE y IN (SELECT a FROM t2) |
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57 | } |
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58 | } {1 2 three scan 0 sort 0} |
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59 | |||
60 | finish_test |