Fix for bug#42009: SELECT into variable gives different results to direct SELECT

Problem: storing "SELECT ... INTO @var ..." results in variables we used val_xxx()
methods which returned results of the current row. 
So, in some cases (e.g. SELECT DISTINCT, GROUP BY or HAVING) we got data
from the first row of a new group (where we evaluate a clause) instead of
data from the last row of the previous group.

Fix: use val_xxx_result() counterparts to get proper results.


mysql-test/r/distinct.result:
  Fix for bug#42009: SELECT into variable gives different results to direct SELECT
    - results adjusted.
mysql-test/r/user_var.result:
  Fix for bug#42009: SELECT into variable gives different results to direct SELECT
    - test result.
mysql-test/t/user_var.test:
  Fix for bug#42009: SELECT into variable gives different results to direct SELECT
    - test case.
sql/item_func.cc:
  Fix for bug#42009: SELECT into variable gives different results to direct SELECT
    - Item_func_set_user_var::save_item_result() added to evaluate and store 
      an item's result into a user variable.
sql/item_func.h:
  Fix for bug#42009: SELECT into variable gives different results to direct SELECT
    - Item_func_set_user_var::save_item_result() added to evaluate and store 
      an item's result into a user variable.
sql/sql_class.cc:
  Fix for bug#42009: SELECT into variable gives different results to direct SELECT
    - use Item_func_set_user_var::save_item_result() to store results into user 
      variables.

1 files changed, 4 insertions, 4 deletions

diff --git a/mysql-test/r/distinct.result b/mysql-test/r/distinct.result
index 114d3088fe8..ddbee3ec79c 100644
--- a/mysql-test/r/distinct.result
+++ b/mysql-test/r/distinct.result
@@ -629,21 +629,21 @@ SELECT DISTINCT @v5:= fruit_id, @v6:= fruit_name INTO @v7, @v8 FROM t1 WHERE
 fruit_name = 'APPLE';
 SELECT @v5, @v6, @v7, @v8;
 @v5	@v6	@v7	@v8
-3	PEAR	3	PEAR
+2	APPLE	2	APPLE
 SELECT DISTINCT @v5 + fruit_id, CONCAT(@v6, fruit_name) INTO @v9, @v10 FROM t1 
 WHERE fruit_name = 'APPLE';
 SELECT @v5, @v6, @v7, @v8, @v9, @v10;
 @v5	@v6	@v7	@v8	@v9	@v10
-3	PEAR	3	PEAR	5	PEARAPPLE
+2	APPLE	2	APPLE	4	APPLEAPPLE
 SELECT DISTINCT @v11:= @v5 + fruit_id, @v12:= CONCAT(@v6, fruit_name) INTO 
 @v13, @v14 FROM t1 WHERE fruit_name = 'APPLE';
 SELECT @v11, @v12, @v13, @v14;
 @v11	@v12	@v13	@v14
-6	PEARPEAR	6	PEARPEAR
+4	APPLEAPPLE	4	APPLEAPPLE
 SELECT DISTINCT @v13, @v14 INTO @v15, @v16 FROM t1 WHERE fruit_name = 'APPLE';
 SELECT @v15, @v16;
 @v15	@v16
-6	PEARPEAR
+4	APPLEAPPLE
 SELECT DISTINCT 2 + 2, 'Bob' INTO @v17, @v18 FROM t1 WHERE fruit_name = 
 'APPLE';
 SELECT @v17, @v18;