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DB2 存储过程中执行动态SQL的两种写法

发表于:2025-01-22 作者:千家信息网编辑
千家信息网最后更新 2025年01月22日,样本代码:DROP PROCEDURE QUOTATION.COPY_SAMPLE;CREATE PROCEDURE QUOTATION.COPY_SAMPLE ( IN tableNameFr
千家信息网最后更新 2025年01月22日DB2 存储过程中执行动态SQL的两种写法

样本代码:

DROP PROCEDURE QUOTATION.COPY_SAMPLE;CREATE PROCEDURE QUOTATION.COPY_SAMPLE (    IN tableNameFrom VARCHAR(30)    , IN tableNameTo VARCHAR(30)    , INOUT copyResult INTEGER)BEGIN    DECLARE SQLCODE INTEGER DEFAULT 0;    SET copyResult = 0;    -- Proecss 1    BEGIN        DECLARE fromSql VARCHAR(32672);        DECLARE toSql VARCHAR(32672);        DECLARE seqTo VARCHAR(30);        DECLARE templateParserId INTEGER;        DECLARE uuid VARCHAR(36);        DECLARE stmt STATEMENT;        DECLARE curs CURSOR FOR stmt;        SET seqTo = 'SEQ_' || tableNameTo;        SET fromSql = 'SELECT MAX(TEMPLATE_PARSER_ID), UUID FROM QUOTATION.' || tableNameFrom || ' GROUP BY UUID';        PREPARE stmt FROM fromSql;        OPEN curs;        CURSORLOOP:            LOOP                FETCH curs INTO templateParserId, uuid;                -- Do nothing if no data or processed all datas.                IF SQLCODE = 100 THEN LEAVE CURSORLOOP;                END IF;                SET uuid = (SELECT CONCAT(HEX(RAND()), HEX(RAND())) FROM SYSIBM.SYSDUMMY1);                SET toSql = 'INSERT INTO QUOTATION.' || tableNameTo || ' (TEMPLATE_PARSER_ID, UUID) VALUES (NEXTVAL FOR QUOTATION.' || seqTo || ',''' || uuid || ''')';                PREPARE s FROM toSql;                EXECUTE s;            END LOOP;        CLOSE curs;    END;    -- Proecss 2    BEGIN        -- ......    END;    SET copyResult = 1;END;

注意点:
1、SQLCODE必须要定义,且必须定义在最外层的BEGIN的下面。
2、必须要判断SQLCODE是否等于100,等于100时退出CURSORLOOP,否则会死循环。
3、"OPEN curs"之后不要忘记"CURSORLOOP:"。

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