Question

我有30个表，即second_data_0，second_data_1，..........，second_data_29。我将这些表与另一个表first_data逐个连接，并将结果存储在Mysql存储过程的临时表中（如下所示）。有人能告诉我如何在oracle程序中执行此操作，尤其是SET @s = CONCAT("INSERT INTO firstTemp SELECT a.ID,b.CLSNO,b.FEES,b.FEES_T,b.FEES_DT FROM first_data a, second_data_",i," b WHERE a.CLASS_NO = b.CLSNO AND (b.FEES < a.FEES_AMOUNT) AND b.FEES_DT BETWEEN DATE('2017-11-20') AND DATE('2017-12-25')");部分吗？

    SET i = 1;
CREATE TEMPORARY TABLE firstTemp
SELECT a.ID,b.CLSNO,b.FEES,b.FEES_T,b.FEES_DT FROM first_data a, second_data_0 b WHERE a.CLASS_NO = b.CLSNO AND (b.FEES < a.FEES_AMOUNT) AND b.FEES_DT BETWEEN DATE('2017-11-20') AND DATE('2017-12-25');
label1: WHILE i < 30 DO
    SET @s = CONCAT("INSERT INTO firstTemp SELECT a.ID,b.CLSNO,b.FEES,b.FEES_T,b.FEES_DT FROM first_data a, second_data_",i," b WHERE a.CLASS_NO = b.CLSNO AND (b.FEES < a.FEES_AMOUNT) AND b.FEES_DT BETWEEN DATE('2017-11-20') AND DATE('2017-12-25')");
    PREPARE stmt1 FROM @s;
    EXECUTE stmt1;
    DEALLOCATE PREPARE stmt1; 
    SET i = i + 1;
END WHILE label1;

Answer 1

试试这个

stmt := 'CREATE TEMPORARY TABLE firstTemp(list if columns) ON COMMIT DELETE ROWS';
execute immediate stmt;

WHILE (i < 30) loop
stmt2 := 'INSERT INTO firstTemp values( SELECT a.ID,b.CLSNO,b.FEES,b.FEES_T,b.FEES_DT FROM first_data a, second_data_' || i ||
         ' b WHERE a.CLASS_NO = b.CLSNO AND (b.FEES < a.FEES_AMOUNT) AND b.FEES_DT BETWEEN DATE(''2017-11-20'') AND DATE(''2017-12-25''))';
execute immediate stmt2;
i := i + 1;
end loop;

stmt和stmt2都是长变量，i是整数。

Answer 2

开始之前的一个重要提示：请勿使用JOINS的逗号（a，b）语法，使用JOIN ON语法。

您可以在PL / SQL中使用数字FOR LOOP。

BEGIN
       EXECUTE IMMEDIATE
          '
    CREATE GLOBAL TEMPORARY TABLE firstTemp

    AS
       SELECT a.ID,
              b.CLSNO,
              b.FEES,
              b.FEES_T,
              b.FEES_DT
         FROM first_data a
              JOIN second_data_0 b
                 ON a.CLASS_NO = b.CLSNO AND b.FEES < a.FEES_AMOUNT
        WHERE b.FEES_DT BETWEEN DATE ''2017-11-20'' AND DATE ''2017-12-25''';

       FOR i IN 1 .. 30
       LOOP
          EXECUTE IMMEDIATE
                '
    INSERT INTO firstTemp
       SELECT a.ID,
              b.CLSNO,
              b.FEES,
              b.FEES_T,
              b.FEES_DT
         FROM first_data a JOIN second_data_'
         || i
         || ' b ON a.CLASS_NO = b.CLSNO AND b.FEES < a.FEES_AMOUNT WHERE b.FEES_DT
BETWEEN DATE ''2017-11-20'' AND DATE ''2017-12-25''';
   END LOOP;
END;

用于在oracle中执行动态查询的表名串联

2 个答案: