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From:Patrick Galbraith Date:August 8 2005 8:46pm
Subject:bk commit into 4.1 tree (patg:1.2367) BUG#11104
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Below is the list of changes that have just been committed into a local
4.1 repository of patg. When patg does a push these changes will
be propagated to the main repository and, within 24 hours after the
push, to the public repository.
For information on how to access the public repository
see http://dev.mysql.com/doc/mysql/en/installing-source-tree.html

ChangeSet
  1.2367 05/08/08 13:46:13 patg@stripped +3 -0
  item_strfunc.cc:
    BUG #11104 
        Took out the offset-=delimiter_length-1 out of the for loop. It was causing
        basically this: 
        select substring_index('the king of the the hill', 'the', -2) to not work.
        The first iteration, offset would be initialised to 24, then strstr would 
        point at 'the king of the the* hill' ('*'means right before the 
        character following), returning a offset of 16. The for loop would then 
        decrement offset by two (3 - 1), to 14, now pointing at 
        "the king of th*e the hill", _skipping_ past the 'e' in the second to last
        'the', and therefore strstr would never have a chance of matching the 
        second to last 'the', then moving on to the 'the' at the begginning of the 
        string!
        In a nutshell, offset was being decremented by too great a value, preventing
        the second to last 'the' from being ever found, hence the result of 
        'king of the the hill' from the query that is reported in the bug report
  func_str.test:
    BUG #11104
    Added tests to make sure fix addresses issues in original bug report
  func_str.result:
    BUG #11104 
    New results for new tests

  sql/item_strfunc.cc
    1.234 05/08/08 13:44:40 patg@stripped +14 -2
    BUG #11104 
        Took out the offset-=delimiter_length-1 out of the for loop. It was causing
        basically this: 
        select substring_index('the king of the the hill', 'the', -2) to not work.
        The first iteration, offset would be initialised to 24, then strstr would 
        point at 'the king of the the* hill' ('*'means right before the 
        character following), returning a offset of 16. The for loop would then 
        decrement offset by two (3 - 1), to 14, now pointing at 
        "the king of th*e the hill", _skipping_ past the 'e' in the second to last
        'the', and therefore strstr would never have a chance of matching the 
        second to last 'the', then moving on to the 'the' at the begginning of the 
        string!
    
        In a nutshell, offset was being decremented by too great a value, preventing
        the second to last 'the' from being ever found, hence the result of 
        'king of the the hill' from the query that is reported in the bug report

  mysql-test/t/func_str.test
    1.79 05/08/08 13:44:40 patg@stripped +39 -0
    BUG #11104
    
    Added tests to make sure fix addresses issues in original bug report

  mysql-test/r/func_str.result
    1.97 05/08/08 13:44:40 patg@stripped +117 -0
    BUG #11104 
    
    New results for new tests

# This is a BitKeeper patch.  What follows are the unified diffs for the
# set of deltas contained in the patch.  The rest of the patch, the part
# that BitKeeper cares about, is below these diffs.
# User:	patg
# Host:	krsna.patg.net
# Root:	/home/patg/mysql-build/mysql-4.1

--- 1.233/sql/item_strfunc.cc	2005-07-22 11:46:25 -07:00
+++ 1.234/sql/item_strfunc.cc	2005-08-08 13:44:40 -07:00
@@ -42,7 +42,7 @@
                               const char *fname)
 {
   my_error(ER_CANT_AGGREGATE_2COLLATIONS,MYF(0),
-  	   c1.collation->name,c1.derivation_name(),
+	   c1.collation->name,c1.derivation_name(),
 	   c2.collation->name,c2.derivation_name(),
 	   fname);
 }
@@ -1188,10 +1188,22 @@
     }
     else
     {					// Start counting at end
-      for (offset=res->length() ; ; offset-=delimeter_length-1)
+      /*
+        Negative index, start counting at the end
+      */
+      for (offset=res->length(); offset ;)
       {
+        /* 
+          this call will result in finding the position pointing to one 
+          address space less than where the found substring is located
+          in res
+        */
 	if ((int) (offset=res->strrstr(*delimeter,offset)) < 0)
 	  return res;			// Didn't find, return org string
+        /*
+          At this point, we've searched for the substring
+          the number of times as supplied by the index value
+        */
 	if (!++count)
 	{
 	  offset+=delimeter_length;

--- 1.96/mysql-test/r/func_str.result	2005-07-22 11:46:25 -07:00
+++ 1.97/mysql-test/r/func_str.result	2005-08-08 13:44:40 -07:00
@@ -45,6 +45,123 @@
 select substring_index('.tcx.se','.',-2),substring_index('.tcx.se','.tcx',-1);
 substring_index('.tcx.se','.',-2)	substring_index('.tcx.se','.tcx',-1)
 tcx.se	.se
+select substring_index('aaaaaaaaa1','a',1);
+substring_index('aaaaaaaaa1','a',1)
+
+select substring_index('aaaaaaaaa1','aa',1);
+substring_index('aaaaaaaaa1','aa',1)
+
+select substring_index('aaaaaaaaa1','aa',2);
+substring_index('aaaaaaaaa1','aa',2)
+aa
+select substring_index('aaaaaaaaa1','aa',3);
+substring_index('aaaaaaaaa1','aa',3)
+aaaa
+select substring_index('aaaaaaaaa1','aa',4);
+substring_index('aaaaaaaaa1','aa',4)
+aaaaaa
+select substring_index('aaaaaaaaa1','aa',5);
+substring_index('aaaaaaaaa1','aa',5)
+aaaaaaaaa1
+select substring_index('aaaaaaaaa1','aaa',1);
+substring_index('aaaaaaaaa1','aaa',1)
+
+select substring_index('aaaaaaaaa1','aaa',2);
+substring_index('aaaaaaaaa1','aaa',2)
+aaa
+select substring_index('aaaaaaaaa1','aaa',3);
+substring_index('aaaaaaaaa1','aaa',3)
+aaaaaa
+select substring_index('aaaaaaaaa1','aaa',4);
+substring_index('aaaaaaaaa1','aaa',4)
+aaaaaaaaa1
+select substring_index('aaaaaaaaa1','aaaa',1);
+substring_index('aaaaaaaaa1','aaaa',1)
+
+select substring_index('aaaaaaaaa1','aaaa',2);
+substring_index('aaaaaaaaa1','aaaa',2)
+aaaa
+select substring_index('aaaaaaaaa1','1',1);
+substring_index('aaaaaaaaa1','1',1)
+aaaaaaaaa
+select substring_index('aaaaaaaaa1','a',-1);
+substring_index('aaaaaaaaa1','a',-1)
+1
+select substring_index('aaaaaaaaa1','aa',-1);
+substring_index('aaaaaaaaa1','aa',-1)
+1
+select substring_index('aaaaaaaaa1','aa',-2);
+substring_index('aaaaaaaaa1','aa',-2)
+aa1
+select substring_index('aaaaaaaaa1','aa',-3);
+substring_index('aaaaaaaaa1','aa',-3)
+aaaa1
+select substring_index('aaaaaaaaa1','aa',-4);
+substring_index('aaaaaaaaa1','aa',-4)
+aaaaaa1
+select substring_index('aaaaaaaaa1','aa',-5);
+substring_index('aaaaaaaaa1','aa',-5)
+aaaaaaaaa1
+select substring_index('aaaaaaaaa1','aaa',-1);
+substring_index('aaaaaaaaa1','aaa',-1)
+1
+select substring_index('aaaaaaaaa1','aaa',-2);
+substring_index('aaaaaaaaa1','aaa',-2)
+aaa1
+select substring_index('aaaaaaaaa1','aaa',-3);
+substring_index('aaaaaaaaa1','aaa',-3)
+aaaaaa1
+select substring_index('aaaaaaaaa1','aaa',-4);
+substring_index('aaaaaaaaa1','aaa',-4)
+
+select substring_index('the king of thethe hill','the',-2);
+substring_index('the king of thethe hill','the',-2)
+the hill
+select substring_index('the king of the the hill','the',-2);
+substring_index('the king of the the hill','the',-2)
+ the hill
+select substring_index('the king of the  the hill','the',-2);
+substring_index('the king of the  the hill','the',-2)
+  the hill
+select substring_index('the king of the  the hill',' the ',-1);
+substring_index('the king of the  the hill',' the ',-1)
+hill
+select substring_index('the king of the  the hill',' the ',-2);
+substring_index('the king of the  the hill',' the ',-2)
+ the hill
+select substring_index('the king of the  the hill',' ',-1);
+substring_index('the king of the  the hill',' ',-1)
+hill
+select substring_index('the king of the  the hill',' ',-2);
+substring_index('the king of the  the hill',' ',-2)
+the hill
+select substring_index('the king of the  the hill',' ',-3);
+substring_index('the king of the  the hill',' ',-3)
+ the hill
+select substring_index('the king of the  the hill',' ',-4);
+substring_index('the king of the  the hill',' ',-4)
+the  the hill
+select substring_index('the king of the  the hill',' ',-5);
+substring_index('the king of the  the hill',' ',-5)
+of the  the hill
+select substring_index('the king of the.the hill','the',-2);
+substring_index('the king of the.the hill','the',-2)
+.the hill
+select substring_index('the king of thethethe.the hill','the',-3);
+substring_index('the king of thethethe.the hill','the',-3)
+the.the hill
+select substring_index('the king of thethethe.the hill','the',-1);
+substring_index('the king of thethethe.the hill','the',-1)
+ hill
+select substring_index('the king of the the hill','the',1);
+substring_index('the king of the the hill','the',1)
+
+select substring_index('the king of the the hill','the',2);
+substring_index('the king of the the hill','the',2)
+the king of 
+select substring_index('the king of the the hill','the',3);
+substring_index('the king of the the hill','the',3)
+the king of the 
 select concat(':',ltrim('  left  '),':',rtrim('  right  '),':');
 concat(':',ltrim('  left  '),':',rtrim('  right  '),':')
 :left  :  right:

--- 1.78/mysql-test/t/func_str.test	2005-07-27 17:21:42 -07:00
+++ 1.79/mysql-test/t/func_str.test	2005-08-08 13:44:40 -07:00
@@ -23,6 +23,45 @@
 select substring_index('www.tcx.se','.',-2),substring_index('www.tcx.se','.',1);
 select substring_index('www.tcx.se','tcx',1),substring_index('www.tcx.se','tcx',-1);
 select substring_index('.tcx.se','.',-2),substring_index('.tcx.se','.tcx',-1);
+select substring_index('aaaaaaaaa1','a',1);
+select substring_index('aaaaaaaaa1','aa',1);
+select substring_index('aaaaaaaaa1','aa',2);
+select substring_index('aaaaaaaaa1','aa',3);
+select substring_index('aaaaaaaaa1','aa',4);
+select substring_index('aaaaaaaaa1','aa',5);
+select substring_index('aaaaaaaaa1','aaa',1);
+select substring_index('aaaaaaaaa1','aaa',2);
+select substring_index('aaaaaaaaa1','aaa',3);
+select substring_index('aaaaaaaaa1','aaa',4);
+select substring_index('aaaaaaaaa1','aaaa',1);
+select substring_index('aaaaaaaaa1','aaaa',2);
+select substring_index('aaaaaaaaa1','1',1);
+select substring_index('aaaaaaaaa1','a',-1);
+select substring_index('aaaaaaaaa1','aa',-1);
+select substring_index('aaaaaaaaa1','aa',-2);
+select substring_index('aaaaaaaaa1','aa',-3);
+select substring_index('aaaaaaaaa1','aa',-4);
+select substring_index('aaaaaaaaa1','aa',-5);
+select substring_index('aaaaaaaaa1','aaa',-1);
+select substring_index('aaaaaaaaa1','aaa',-2);
+select substring_index('aaaaaaaaa1','aaa',-3);
+select substring_index('aaaaaaaaa1','aaa',-4);
+select substring_index('the king of thethe hill','the',-2);
+select substring_index('the king of the the hill','the',-2);
+select substring_index('the king of the  the hill','the',-2);
+select substring_index('the king of the  the hill',' the ',-1);
+select substring_index('the king of the  the hill',' the ',-2);
+select substring_index('the king of the  the hill',' ',-1);
+select substring_index('the king of the  the hill',' ',-2);
+select substring_index('the king of the  the hill',' ',-3);
+select substring_index('the king of the  the hill',' ',-4);
+select substring_index('the king of the  the hill',' ',-5);
+select substring_index('the king of the.the hill','the',-2);
+select substring_index('the king of thethethe.the hill','the',-3);
+select substring_index('the king of thethethe.the hill','the',-1);
+select substring_index('the king of the the hill','the',1);
+select substring_index('the king of the the hill','the',2);
+select substring_index('the king of the the hill','the',3);
 
 select concat(':',ltrim('  left  '),':',rtrim('  right  '),':');
 select concat(':',trim(LEADING FROM ' left'),':',trim(TRAILING FROM ' right '),':');
Thread
bk commit into 4.1 tree (patg:1.2367) BUG#11104Patrick Galbraith8 Aug