Commit 60496497 authored by unknown's avatar unknown
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Fix for BUG#8490: In mysql_make_view for join algorithm views we need 

to insert view's subqueries into select_lex->slave(->next)* chain. 
In case a join has several such views, don't add the same subqueries several times
(this forms a loop on the above chain which breaks many parts of the code)


mysql-test/r/view.result:
  Testcase for BUG#8490
mysql-test/t/view.test:
  Testcase for BUG#8490
parent 241bedad

mysql-test/r/view.result

+18 −0
Original line number Diff line number Diff line
@@ -1694,3 +1694,21 @@ col1 col2 col2 col3 
5	david	NULL	NULL

DROP VIEW v1,v2,v3;

DROP TABLE t1,t2;

create table t1 as select 1 A union select 2 union select 3;

create table t2 as select * from t1;

create view v1 as select * from t1 where a in (select * from t2);

select * from v1 A, v1 B where A.a = B.a;

A	A

1	1

2	2

3	3

create table t3 as select a a,a b from t2;

create view v2 as select * from t3 where 

a in (select * from t1) or b in (select * from t2);

select * from v2 A, v2 B where A.a = B.b;

a	b	a	b

1	1	1	1

2	2	2	2

3	3	3	3

drop view v1, v2;

drop table t1, t2, t3;

mysql-test/t/view.test

+14 −0
Original line number Diff line number Diff line
@@ -1519,3 +1519,17 @@ SELECT a.col1,a.col2,b.col2,b.col3 
 

DROP VIEW v1,v2,v3;

DROP TABLE t1,t2;



# BUG#8490 Select from views containing subqueries causes server to hang 

# forever.

create table t1 as select 1 A union select 2 union select 3;

create table t2 as select * from t1;

create view v1 as select * from t1 where a in (select * from t2);

select * from v1 A, v1 B where A.a = B.a;

create table t3 as select a a,a b from t2;

create view v2 as select * from t3 where 

  a in (select * from t1) or b in (select * from t2);

select * from v2 A, v2 B where A.a = B.b;

drop view v1, v2;

drop table t1, t2, t3;

sql/sql_view.cc

+11 −3
Original line number Diff line number Diff line
@@ -796,17 +796,25 @@ mysql_make_view(File_parser *parser, TABLE_LIST *table) 


      /* Store WHERE clause for post-processing in setup_ancestor */

      table->where= view_select->where;



      /*

        Add subqueries units to SELECT in which we merging current view.

        Add subqueries units to SELECT into which we merging current view.

        

        unit(->next)* chain starts with subqueries that are used by this

        view and continues with subqueries that are used by other views.

        We must not add any subquery twice (otherwise we'll form a loop),

        to do this we remember in end_unit the first subquery that has 

        been already added.

                

        NOTE: we do not support UNION here, so we take only one select

      */

      SELECT_LEX_NODE *end_unit= table->select_lex->slave;

      for (SELECT_LEX_UNIT *unit= lex->select_lex.first_inner_unit();

           unit;

           unit= unit->next_unit())

      {

        SELECT_LEX_NODE *save_slave= unit->slave;

        if (unit == end_unit)

          break;

        unit->include_down(table->select_lex);

        unit->slave= save_slave; // fix include_down initialisation

      }