database/mariadb
1
0
Fork 0
mirror of https://github.com/MariaDB/server.git synced 2025-07-30 16:24:05 +03:00
Code Activity

Fix for Bug#30217: Views: changes in metadata behaviour

Browse Source 
between 5.0 and 5.1.
  
The problem was that in the patch for Bug#11986 it was decided
to store original query in UTF8 encoding for the INFORMATION_SCHEMA.
This approach however turned out to be quite difficult to implement
properly. The main problem is to preserve the same IS-output after
dump/restore.
  
So, the fix is to rollback to the previous functionality, but also
to fix it to support multi-character-set-queries properly. The idea
is to generate INFORMATION_SCHEMA-query from the item-tree after
parsing view declaration. The IS-query should:
  - be completely in UTF8;
  - not contain character set introducers.
  
For more information, see WL4052.
This commit is contained in:
anozdrin/alik@quad.
2008-02-22 13:30:33 +03:00
parent 10dca4fd8d
commit 340906f46d
39 changed files with 709 additions and 380 deletions
Download Patch File Download Diff File Expand all files Collapse all files

48
sql/sql_view.cc
View File

@ -720,7 +720,42 @@ static int mysql_register_view(THD *thd, TABLE_LIST *view,
{
LEX *lex= thd->lex;
char buff[4096];
String view_query(buff, sizeof (buff), thd->charset());
/*
View definition query -- a SELECT statement that fully defines view. It
is generated from the Item-tree built from the original (specified by
the user) query. The idea is that generated query should eliminates all
ambiguities and fix view structure at CREATE-time (once for all).
Item::print() virtual operation is used to generate view definition
query.
INFORMATION_SCHEMA query (IS query) -- a SQL statement describing a
view that is shown in INFORMATION_SCHEMA. Basically, it is 'view
definition query' with text literals converted to UTF8 and without
character set introducers.
For example:
Let's suppose we have:
CREATE TABLE t1(a INT, b INT);
User specified query:
CREATE VIEW v1(x, y) AS SELECT * FROM t1;
Generated query:
SELECT a AS x, b AS y FROM t1;
IS query:
SELECT a AS x, b AS y FROM t1;
View definition query is stored in the client character set.
*/
char view_query_buff[4096];
String view_query(view_query_buff,
sizeof (view_query_buff),
thd->charset());
char is_query_buff[4096];
String is_query(is_query_buff,
sizeof (is_query_buff),
system_charset_info);
char md5[MD5_BUFF_LENGTH];
bool can_be_merged;
char dir_buff[FN_REFLEN], path_buff[FN_REFLEN];
@ -728,12 +763,16 @@ static int mysql_register_view(THD *thd, TABLE_LIST *view,
int error= 0;
DBUG_ENTER("mysql_register_view");
/* print query */
/* Generate view definition and IS queries. */
view_query.length(0);
is_query.length(0);
{
ulong sql_mode= thd->variables.sql_mode & MODE_ANSI_QUOTES;
thd->variables.sql_mode&= ~MODE_ANSI_QUOTES;
lex->unit.print(&view_query);
lex->unit.print(&view_query, QT_ORDINARY);
lex->unit.print(&is_query, QT_IS);
thd->variables.sql_mode|= sql_mode;
}
DBUG_PRINT("info", ("View: %s", view_query.ptr()));
@ -872,7 +911,8 @@ loop_out:
lex_string_set(&view->view_connection_cl_name,
view->view_creation_ctx->get_connection_cl()->name);
view->view_body_utf8= lex->view_body_utf8;
view->view_body_utf8.str= is_query.c_ptr_safe();
view->view_body_utf8.length= is_query.length();
/*
Check that table of main select do not used in subqueries.