Oracle 5.0 Reference Manual page 1223

SHOW VARIABLES LIKE 'max_join_size';
SHOW SESSION VARIABLES LIKE 'max_join_size';
To get a list of variables whose name match a pattern, use the "%" wildcard character in a
clause:
SHOW VARIABLES LIKE '%size%';
SHOW GLOBAL VARIABLES LIKE '%size%';
Wildcard characters can be used in any position within the pattern to be matched. Strictly speaking,
because "_" is a wildcard that matches any single character, you should escape it as "\_" to match it
literally. In practice, this is rarely necessary.
13.7.5.37.
SHOW WARNINGS
SHOW WARNINGS [LIMIT [offset,] row_count]
SHOW COUNT(*) WARNINGS
SHOW WARNINGS
from the last statement in the current session that generated messages. It shows nothing if the last
statement used a table and generated no messages. (That is, a statement that uses a table but
generates no messages clears the message list.) Statements that do not use tables and do not
generate messages have no effect on the message list.
Warnings are generated for DML statements such as INSERT, UPDATE, and
well as DDL statements such as
SHOW WARNINGS
generated by
Output
EXTENDED
The clause has the same syntax as for the
LIMIT
Syntax".
A related statement,
See Section 13.7.5.14,
The
SHOW COUNT(*) WARNINGS
You can also retrieve this number from the
SHOW COUNT(*) WARNINGS;
SELECT @@warning_count;
Here is a simple example that shows a syntax warning for
for INSERT:
mysql> CREATE TABLE t1
> (a TINYINT NOT NULL, b CHAR(4))
> TYPE=MyISAM;
Query OK, 0 rows affected, 1 warning (0.00 sec)
mysql> SHOW WARNINGS\G
*************************** 1. row ***************************
Level: Warning
Code: 1287
Message: 'TYPE=storage_engine' is deprecated, use
'ENGINE=storage_engine' instead
1 row in set (0.00 sec)
mysql> INSERT INTO t1 VALUES(10,'mysql'),
-> (NULL,'test'), (300,'Open Source');
Query OK, 3 rows affected, 4 warnings (0.01 sec)
Records: 3
mysql> SHOW WARNINGS\G
*************************** 1. row ***************************
Level: Warning
Syntax
shows information about the conditions (errors, warnings, and notes) that resulted
CREATE TABLE
is also used following
when the
EXPLAIN EXTENDED
Format".
ERRORS, shows only the error conditions (it excludes warnings and notes).
SHOW
"SHOW ERRORS
statement displays the total number of errors, warnings, and notes.
Duplicates: 0 Warnings: 4
Syntax
SHOW
and
ALTER TABLE.
EXTENDED, to display the extra information
EXPLAIN
keyword is used. See
statement. See
SELECT
Syntax".
[507]
warning_count
CREATE TABLE
1203
LIKE
LOAD DATA INFILE
Section 8.2.3, "EXPLAIN
Section 13.2.8,
system variable:
and conversion warnings
[896]
as
"SELECT