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test/tkt-fa7bf5ec.test

39 строк1 KB

drh

Make sure the query optimizer for aggregate queries knows that expressions

13 окт 2011, 19:35

13 окт 2011, 19:356b93c9a

# 2011 October 13
#
# The author disclaims copyright to this source code.  In place of
# a legal notice, here is a blessing:
#
#    May you do good and not evil.
#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library. Specifically,
# it tests that ticket [fa7bf5ec94801e7e2030e41eefe5d9dd96eaacfd] has
# been resolved.
#
# The problem described by this ticket was that the sqlite3ExprCompare()
# function was saying that expressions (x='a') and (x='A') were identical
# because it was using sqlite3StrICmp() instead of strcmp() to compare string
# literals.  That was causing the query optimizer for aggregate queries to 
# believe that both count() operations were identical, and thus only 
# computing the first count() and making a copy of the result for the 
# second count().
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl

do_test tkt-fa7bf5ec-1 {
  execsql {
    CREATE TABLE t1(x);
    INSERT INTO t1 VALUES ('a');
    INSERT INTO t1 VALUES ('A');
    INSERT INTO t1 VALUES ('A');
    SELECT count(CASE WHEN x='a' THEN 1 END),
           count(CASE WHEN x='A' THEN 1 END)
      FROM t1;
  }
} {1 2}

finish_test