Oracle（SQL语句）-使用WHERE子句的CASE

各位专家:， 我正在准备一个SQL报告，以使用CASE检查验证的格式显示数据。我提供了以下示例、问题和期望：

表格结构：

SELECT 

ID,PRODUCT,COMMENTS

CASE WHEN SUBSTR(COMMENTS,1,35)=REGEXP_SUBSTR (COMMENTS,'(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\s)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\s)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\s)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\d)',1,1)
AND
LENGTH(TRIM(REGEXP_SUBSTR (COMMENTS, '(\S*)(\s)', 1, 2)))=8 
AND
REGEXP_LIKE(TRIM(REGEXP_SUBSTR (COMMENTS, '(\S*)(\s)', 1, 1)),'(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\d)')
THEN 'Correct Format'
ELSE 'Incorrect_Format'
END AS Format_Check

FROM TEST_TABLE

SQL语句：

SELECT 

ID,PRODUCT,COMMENTS

CASE WHEN SUBSTR(COMMENTS,1,35)=REGEXP_SUBSTR (COMMENTS,'(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\s)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\s)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\s)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\d)',1,1)
AND
LENGTH(TRIM(REGEXP_SUBSTR (COMMENTS, '(\S*)(\s)', 1, 2)))=8 
AND
REGEXP_LIKE(TRIM(REGEXP_SUBSTR (COMMENTS, '(\S*)(\s)', 1, 1)),'(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\d)')
THEN 'Correct Format'
ELSE 'Incorrect_Format'
END AS Format_Check

FROM TEST_TABLE

SQL输出：

SQL输出说明：

SELECT 

ID,PRODUCT,COMMENTS

CASE WHEN SUBSTR(COMMENTS,1,35)=REGEXP_SUBSTR (COMMENTS,'(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\s)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\s)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\s)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\d)',1,1)
AND
LENGTH(TRIM(REGEXP_SUBSTR (COMMENTS, '(\S*)(\s)', 1, 2)))=8 
AND
REGEXP_LIKE(TRIM(REGEXP_SUBSTR (COMMENTS, '(\S*)(\s)', 1, 1)),'(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\d)')
THEN 'Correct Format'
ELSE 'Incorrect_Format'
END AS Format_Check

FROM TEST_TABLE

检查注释列是否为35个字符长，还检查格式编号和空格。SUBSTR（注释，1,35）=REGEXP\u SUBSTR 注释，（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\s）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）1）

检查第一个空格后的注释长度是否为8个字符（TRIM（REGEXP_SUBSTR（注释，（\S*）（\S*），1，2））=8

检查前8个字符是否为数字/数字。REGEXP_LIKE（TRIM（REGEXP_SUBSTR）（注释，（\S*）（\S）），1， 1） ），“（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）（\d）”）

期望值：

SELECT 

ID,PRODUCT,COMMENTS

CASE WHEN SUBSTR(COMMENTS,1,35)=REGEXP_SUBSTR (COMMENTS,'(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\s)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\s)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\s)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\d)',1,1)
AND
LENGTH(TRIM(REGEXP_SUBSTR (COMMENTS, '(\S*)(\s)', 1, 2)))=8 
AND
REGEXP_LIKE(TRIM(REGEXP_SUBSTR (COMMENTS, '(\S*)(\s)', 1, 1)),'(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\d)')
THEN 'Correct Format'
ELSE 'Incorrect_Format'
END AS Format_Check

FROM TEST_TABLE

我只需要在执行SQL时显示“格式不正确”的注释，我不希望看到“格式正确”的注释。但是，我需要您的建议，说明这个案例是否与WHERE子句一起使用，以便仅显示不正确的格式注释。 我提到了以前有关WHERE和CASE的查询，但是我不知道如何在WHERE子句中传递我的CASE。

---

谢谢您的帮助。

如果您根本不希望在结果中看到正确的格式，那么您可以在

选择
子句中省略格式的计算。而是在
Where
子句中使用它，如下所示：

SELECT ID,
       PRODUCT,
       COMMENTS,
      'Incorrect_Format' AS format_check
  FROM TEST_TABLE
 WHERE CASE WHEN SUBSTR(COMMENTS,1,35)=REGEXP_SUBSTR (COMMENTS,'(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\s)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\s)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\s)(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\d)',1,1)
AND
LENGTH(TRIM(REGEXP_SUBSTR (COMMENTS, '(\S*)(\s)', 1, 2)))=8 
AND
REGEXP_LIKE(TRIM(REGEXP_SUBSTR (COMMENTS, '(\S*)(\s)', 1, 1)),'(\d)(\d)(\d)(\d)(\d)(\d)(\d)(\d)')
THEN 'Correct Format'
ELSE 'Incorrect_Format'
END AS = 'Incorrect_Format'

如果要显示格式不正确的列，可以使用另一个列包装查询：

SELECT id, product, comment, format_check
  FROM (
        SELECT id, product, comment, CASE WHEN .... END AS format_check
          FROM test_table
       )
 WHERE format_check = 'Incorrect_Format';

顺便说一句，如果使用SQL而不是图像显示表和数据，您的问题更容易回答，例如：

CREATE TABLE test_table (id NUMBER, product VARCHAR2(10), comments VARCHAR2(50));
INSERT INTO  test_table VALUES (1,'Laptop', '00000001 01012020 02022020 03032020');
INSERT INTO  test_table VALUES (1,'PC',     '   00000001 01012020 02022020 0034');

此外，我相信正则表达式可以简化。请提供更多的细节，如果你有兴趣