OracleºÍMSSQLÖÐÑ»·µÄʹÓÃ
ORACLE
CREATE OR REPLACE FUNCTION SETSTATE(OLDVALUE VARCHAR2, POS NUMBER, SVALUE VARCHAR2)
RETURN VARCHAR2
IS
RETURN_VALUE VARCHAR2 (20);
LEN NUMBER(8);
I NUMBER(8);
TEMP_VALUE VARCHAR2(1);
BEGIN
LEN := LENGTH(OLDVALUE);
IF POS > LEN THEN
RETURN 'Ö¸¶¨µÄË÷Òý´óÓÚ×Ö·û´®µÄ³¤¶È£¡';
END IF;
I := 0;
RETURN_VALUE := '';
FOR I IN 1..LEN LOOP
TEMP_VALUE := SUBSTR(OLDVALUE, I, 1);
IF I = POS THEN
TEMP_VALUE := SVALUE;
END IF;
RETURN_VALUE := RETURN_VALUE || TEMP_VALUE;
END LOOP;
RETURN RETURN_VALUE;
END;
MSSQL
IF EXISTS(SELECT * from SYSOBJECTS WHERE NAME = 'SETSTATE')
DROP FUNCTION SETSTATE
GO
CREATE FUNCTION SETSTATE(@OLDVALUE NVARCHAR(20), @POS INT, @SVALUE NVARCHAR(1))
RETURNS NVARCHAR(20)
AS
BEGIN
DECLARE @RETURN_VALUE NVARCHAR(20),
@LENGTH INT,
@I INT,
@TEMP_VALUE NVARCHAR(1);
SET @LENGTH = LEN(@OLDVALUE);
SET @I = 1;
SET @RETURN_VALUE = '';
IF(@POS > @LENGTH)
SET @RETURN_VALUE = @OLDVALUE;
ELSE
BEGIN
WHILE(@I <= @LENGTH)
BEGIN
SET @TEMP_VALUE = SUBSTRING(@OLDVALUE, @I, 1);
IF (@I = @POS)
SET @TEMP_VALUE = @SVALUE;
SET @RETURN_VALUE = @RETURN_VALUE + @TEMP_VALUE;
SET @I = @I + 1;
END
END
RETURN @RETURN_VALUE;
END
GO
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