sql - 結果が null の AND 条件

Question

以下のコードには複数の where 条件が含まれています

select SUM(COMMONSPEC.DISBURSE_AMT)
  from spec_gt1 COMMONSPEC
  where COMMONSPEC.instance_code_1 = 3
  OR COMMONSPEC.instance_code_2 = 3
  OR COMMONSPEC.instance_code_3 = 3
  OR COMMONSPEC.instance_code_4 = 3
  OR COMMONSPEC.instance_code_5 = 3;

いずれかの条件が null を返すため、 AND条件を使用したクエリはnull を返しますが、 OR条件を使用したクエリは異なる結果を返します。サブクエリを書かずにどうすれば達成できますか。何か方法はありますか

Answer 1

あなたはで試すことができAndますis Not null

select SUM(COMMONSPEC.DISBURSE_AMT)
         from spec_gt1 COMMONSPEC
        where (COMMONSPEC.instance_code_1 =
             3 and COMMONSPEC.instance_code_1 is not null)
          OR (COMMONSPEC.instance_code_2 =
              3 and COMMONSPEC.instance_code_2 is not null)
          OR (COMMONSPEC.instance_code_3 =
              3 and COMMONSPEC.instance_code_3 is not null)
          OR (COMMONSPEC.instance_code_4 =
              3 and COMMONSPEC.instance_code_4 is not null)
          OR (COMMONSPEC.instance_code_5 =
              3 and COMMONSPEC.instance_code_5 is not null)

Answer 2

使用できますCOALESCE

SELECT
          SUM ( DISBURSE_AMT )
    FROM
          SPEC_GT1
    WHERE
          COALESCE ( INSTANCE_CODE_1,
                   INSTANCE_CODE_2,
                   INSTANCE_CODE_3,
                   INSTANCE_CODE_4,
                   INSTANCE_CODE_5 ) = 3;

このサンプルを試すことができます:

WITH SPEC_GT1
    AS (SELECT
             1 AS DISBURSE_AMT,
             3 AS INSTANCE_CODE_1,
             3 AS INSTANCE_CODE_2,
             3 AS INSTANCE_CODE_3,
             NULL AS INSTANCE_CODE_4,
             3 AS INSTANCE_CODE_5
        FROM
             DUAL
        UNION ALL
        SELECT
             2 AS DISBURSE_AMT,
             3 AS INSTANCE_CODE_1,
             3 AS INSTANCE_CODE_2,
             3 AS INSTANCE_CODE_3,
             3 AS INSTANCE_CODE_4,
             3 AS INSTANCE_CODE_5
        FROM
             DUAL
        UNION ALL
        SELECT
             3 AS DISBURSE_AMT,
             3 AS INSTANCE_CODE_1,
             NULL AS INSTANCE_CODE_2,
             3 AS INSTANCE_CODE_3,
             3 AS INSTANCE_CODE_4,
             3 AS INSTANCE_CODE_5
        FROM
             DUAL
        UNION ALL
        SELECT
             4 AS DISBURSE_AMT,
             3 AS INSTANCE_CODE_1,
             3 AS INSTANCE_CODE_2,
             2 AS INSTANCE_CODE_3,
             3 AS INSTANCE_CODE_4,
             3 AS INSTANCE_CODE_5
        FROM
             DUAL)
SELECT
      SUM ( DISBURSE_AMT )
FROM
      SPEC_GT1
WHERE
      COALESCE ( INSTANCE_CODE_1,
               INSTANCE_CODE_2,
               INSTANCE_CODE_3,
               INSTANCE_CODE_4,
               INSTANCE_CODE_5 ) = 3

Answer 3

AND および OR 演算子

First of all you have to know about what is AND and OR?
When AND is placed the all columns values are match to 3.

例：

where COMMONSPEC.instance_code_1 = 3
  AND COMMONSPEC.instance_code_2 = 3
  AND COMMONSPEC.instance_code_3 = 3
  AND COMMONSPEC.instance_code_4 = 3
  AND COMMONSPEC.instance_code_5 = 3;

と

When OR is placed if any one column value is match to 3 
then it will show the record.

例：

where COMMONSPEC.instance_code_1 = 3
  OR COMMONSPEC.instance_code_2 = 3
  OR COMMONSPEC.instance_code_3 = 3
  OR COMMONSPEC.instance_code_4 = 3
  OR COMMONSPEC.instance_code_5 = 3;