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【DM版本】:DM Database Server 64 V8
【操作系统】：windows10
【CPU】:
【问题描述】*：触发器编译报错：第 5 行, 第 4 列[FOR]附近出现错误: 语法分析出错，请看下是什么原因

CREATE OR REPLACE TRIGGER "DI_QC_THREE"."TR_UPDATE_XNH_BI_LOG_DV_TAG"
AFTER UPDATE OF DV_TAG
ON QC_BPID_BI_LOG
REFERENCING NEW AS New OLD AS Old
FOR EACH ROW
WHEN (:Old.CLASS_CODE = 'X0100')

DECLARE
    O_V_DV_TAG        INTEGER;
    N_V_DV_TAG        INTEGER;
    V_TABLE_CODE      VARCHAR2(100);
    V_USER_SCHEMA     VARCHAR2(100);
    V_BATCH_NUM       VARCHAR2(100);
    V_SQL             VARCHAR2(2000);
BEGIN
    N_V_DV_TAG := :New.DV_TAG;
    O_V_DV_TAG := :Old.DV_TAG;
    V_USER_SCHEMA := :New.USER_SCHEMA;
    V_TABLE_CODE := :New.TABLE_CODE;
    V_BATCH_NUM := :New.BATCH_NUM;

    IF (O_V_DV_TAG = 0 AND N_V_DV_TAG = 1) THEN
        V_SQL := 'MERGE INTO QC_DV_XNH_INDEX A ' ||
                 'USING (SELECT DOMAIN_CODE, BUSINESS_ID FROM ' || V_USER_SCHEMA || '.' || V_TABLE_CODE || ' WHERE BATCH_NUM = ''' || V_BATCH_NUM || ''') B ' ||
                 'ON (A.DOMAIN_CODE = B.DOMAIN_CODE AND A.TABLE_CODE = ''' || V_TABLE_CODE || ''' AND A.BUSINESS_ID = B.BUSINESS_ID) ' ||
                 'WHEN NOT MATCHED THEN ' ||
                 'INSERT (DOMAIN_CODE, TABLE_CODE, BUSINESS_ID) VALUES (B.DOMAIN_CODE, ''' || V_TABLE_CODE || ''', B.BUSINESS_ID)';

        EXECUTE IMMEDIATE V_SQL;
    END IF;

EXCEPTION
    WHEN OTHERS THEN
        RAISE;
END;