How Can I use Mysql's PROCEDURE by Java Can you give me sample???

Question

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ORACLE�@MSSQL�@SSA�@MySQL�@
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--drop PROCEDURE sp_hoge;
--�f���~�^�����X��������
delimiter //
CREATE PROCEDURE sp_hoge()
DETERMINISTIC
BEGIN
/* �������� */
DECLARE mystr VARCHAR(20);
DECLARE mycnt INTEGER(2);
/* �l������ */
SET mycnt = 0;
SET mystr = '����';
/* IF�� */
IF mycnt = 0 THEN
SET mystr = '�����Q';
select mystr;
ELSE
select '�����R';
END IF;
/* CASE�� */
CASE extract(month from now())
WHEN 1 THEN SET mystr = '1��';
WHEN 2 THEN SET mystr = '2��';
WHEN 3 THEN SET mystr = '3��';
WHEN 4 THEN SET mystr = '4��';
ELSE SET mystr = '1�`4�����O';
END CASE;
select mystr;
/* WHILE-LOOP */
WHILE mycnt <= 5 DO
SET mycnt = mycnt + 1;
select mycnt;
END WHILE;
/* BEGIN-END�u���b�N������SELECT�������s */
/* PROCEDURE�������\�iFUNCTION���������������j */
select * from help_topic;
END//
delimiter ;
--�X�g�A�h�v���V�[�W�����s
call sp_hoge();
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ORACLE�@MSSQL�@SSA�@MySQL�@
�J�[�\�����g�p����LOOP�������T���v�������B
�����p�����[�^���w�����������������Y�������������������A���E���w�X�^�b�t�x�������������A�����������w�c���X�^�b�t�F�x���\���������B
--drop PROCEDURE sp_hoge;
--�f���~�^�����X��������
delimiter //
CREATE PROCEDURE sp_hoge(inum INTEGER(3))
DETERMINISTIC
BEGIN
/* �������� */
/* �J�[�\���g�p�����f�[�^�L�����f���g�p */
DECLARE done INT DEFAULT 0;
/* �������O������ */
DECLARE v_mystr VARCHAR(20);
/* �J�[�\���g�p�� */
DECLARE v_empnm VARCHAR(40);
DECLARE v_job VARCHAR(20);
/* �J�[�\������ �� �����������������`���� */
DECLARE cur1 CURSOR FOR
select empnm,job from kemp where deptno = inum;
/* �f�[�^��������LOOP�E�o�p���������� */
DECLARE CONTINUE HANDLER FOR SQLSTATE '02000' SET done = 1;
/* �J�[�\���I�[�v�� */
OPEN cur1;
/* LOOP */
LOOPPROC:REPEAT
FETCH cur1 INTO v_empnm,v_job;
IF NOT done THEN
IF v_job = '�X�^�b�t' THEN
SET v_mystr = '�c���X�^�b�t�F';
ELSE
SET v_mystr = '';
END IF;
select CONCAT(v_mystr,v_empnm);
/* ������������LOOP���E�o����������LEAVE�� */
/* LEAVE LOOPPROC; */
END IF;
UNTIL done END REPEAT;
/* �J�[�\���N���[�Y */
CLOSE cur1;
END//
--�f���~�^���Z�~�R�����i�f�t�H���g�j������������
delimiter ;
--�X�g�A�h�v���V�[�W�����s
call sp_hoge(1);
12.2. Control Flow Functions
CASE value WHEN [compare_value] THEN result [WHEN [compare_value] THEN result ...] [ELSE result] END
CASE WHEN [condition] THEN result [WHEN [condition] THEN result ...] [ELSE result] END
The first version returns the result where value=compare_value. The second version returns the result for the first condition that is true. If there was no matching result value, the result after ELSE is returned, or NULL if there is no ELSE part.
mysql> SELECT CASE 1 WHEN 1 THEN 'one'
-> WHEN 2 THEN 'two' ELSE 'more' END;
-> 'one'
mysql> SELECT CASE WHEN 1>0 THEN 'true' ELSE 'false' END;
-> 'true'
mysql> SELECT CASE BINARY 'B'
-> WHEN 'a' THEN 1 WHEN 'b' THEN 2 END;
-> NULL
The default return type of a CASE expression is the compatible aggregated type of all return values, but also depends on the context in which it is used. If used in a string context, the result is returned as a string. If used in a numeric context, then the result is returned as a decimal, real, or integer value.
Note: The syntax of the CASE expression shown here differs slightly from that of the SQL CASE statement described in Section 17.2.10.2, �gCASE Statement�h, for use inside stored routines. The CASE statement cannot have an ELSE NULL clause, and it is terminated with END CASE instead of END.
IF(expr1,expr2,expr3)
If expr1 is TRUE (expr1 <> 0 and expr1 <> NULL) then IF() returns expr2; otherwise it returns expr3. IF() returns a numeric or string value, depending on the context in which it is used.
mysql> SELECT IF(1>2,2,3);
-> 3
mysql> SELECT IF(1<2,'yes','no');
-> 'yes'
mysql> SELECT IF(STRCMP('test','test1'),'no','yes');
-> 'no'
If only one of expr2 or expr3 is explicitly NULL, the result type of the IF() function is the type of the non-NULL expression.
expr1 is evaluated as an integer value, which means that if you are testing floating-point or string values, you should do so using a comparison operation.
mysql> SELECT IF(0.1,1,0);
-> 0
mysql> SELECT IF(0.1<>0,1,0);
-> 1
In the first case shown, IF(0.1) returns 0 because 0.1 is converted to an integer value, resulting in a test of IF(0). This may not be what you expect. In the second case, the comparison tests the original floating-point value to see whether it is non-zero. The result of the comparison is used as an integer.
The default return type of IF() (which may matter when it is stored into a temporary table) is calculated as follows:
Expression Return Value
expr2 or expr3 returns a string string
expr2 or expr3 returns a floating-point value floating-point
expr2 or expr3 returns an integer integer
If expr2 and expr3 are both strings, the result is case sensitive if either string is case sensitive.
Note: There is also an IF statement, which differs from the IF() function described here. See Section 17.2.10.1, �gIF Statement�h.
IFNULL(expr1,expr2)
If expr1 is not NULL, IFNULL() returns expr1; otherwise it returns expr2. IFNULL() returns a numeric or string value, depending on the context in which it is used.
mysql> SELECT IFNULL(1,0);
-> 1
mysql> SELECT IFNULL(NULL,10);
-> 10
mysql> SELECT IFNULL(1/0,10);
-> 10
mysql> SELECT IFNULL(1/0,'yes');
-> 'yes'
The default result value of IFNULL(expr1,expr2) is the more �ggeneral�h of the two expressions, in the order STRING, REAL, or INTEGER. Consider the case of a table based on expressions or where MySQL must internally store a value returned by IFNULL() in a temporary table:
mysql> CREATE TABLE tmp SELECT IFNULL(1,'test') AS test;
mysql> DESCRIBE tmp;
-------------------------------------------+
| Field | Type | Null | Key | Default | Extra |
-------------------------------------------+
| test | char(4) | | | | |
-------------------------------------------+
In this example, the type of the test column is CHAR(4).
NULLIF(expr1,expr2)
Returns NULL if expr1 = expr2 is true, otherwise returns expr1. This is the same as CASE WHEN expr1 = expr2 THEN NULL ELSE expr1 END.
mysql> SELECT NULLIF(1,1);
-> NULL
mysql> SELECT NULLIF(1,2);
-> 1
Note that MySQL evaluates expr1 twice if the arguments are not equal.
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User Comments
Posted by I W on July 12 2005 5:52pm [Delete] [Edit]
Don't use IFNULL for comparisons (especially not for Joins)
(example:
select aa from a left join b ON IFNULL(a.col,1)=IFNULL(b.col,1)
It's terrible slow (ran for days on two tables with approx 250k rows).
Use <=> (NULL-safe comparison) instead. It did the same job in less than 15 minutes!!
Posted by [name withheld] on November 10 2005 12:12am [Delete] [Edit]
IFNULL is like oracle's NVL function (these should help people searching for NVL() ..)
Posted by Philip Mak on May 26 2006 7:14am [Delete] [Edit]
When using CASE, remember that NULL != NULL, so if you write "WHEN NULL", it will never match. (I guess you have to use IFNULL() instead...)
Posted by Marc Grue on June 24 2006 2:03pm [Delete] [Edit]
You can ORDER BY a dynamic column_name parameter using a CASE expression in the ORDER BY clause of the SELECT statement:
CREATE PROCEDURE `orderby`(IN _orderby VARCHAR(50))
BEGIN
SELECT id, first_name, last_name, birthday
FROM table
ORDER BY
-- numeric columns
CASE _orderby WHEN 'id' THEN id END ASC,
CASE orderby WHEN 'desc id' THEN id END DESC,
-- string columns
CASE orderby WHEN 'firstname' THEN first_name WHEN 'last_name' THEN last_name END ASC,
CASE orderby WHEN 'descfirst_name' THEN first_name WHEN 'desc_last_name' THEN last_name END DESC,
-- datetime columns
CASE _orderby WHEN 'birthday' THEN birthday END ASC,
CASE orderby WHEN 'desc birthday' THEN birthday END DESC;
END
Since the CASE expression returns the "compatible aggregated type of all return values", you need to isolate each column type in a separate CASE expression to get the desired result.
If you mixed the columns like
CASE _orderby
WHEN 'id' THEN id
WHEN 'first_name' THEN first_name
...etc...
END ASC
.. both the id and first_name would be returned as a string value, and ids would be sorted as a string to '1,12,2,24,5' and not as integers to '1,2,5,12,24'.
Note that you don't need a "ELSE null" in the CASE expressions, since the CASE expression automatically returns null if there's no match. In that case, you get a "null ASC" in your ORDER BY clause which doesn't affect the sort order. If for instance orderby is 'descfirst_name', the ORDER BY clause evaluates to:
ORDER BY null ASC, null DESC, null ASC, first_name DESC, null ASC, null DESC
Effectively the same as "ORDER BY first_name DESC". You could even add a new set of CASE expressions for a second order column (or more..) if you like.
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Answer 1

What is that post supposed to be?