如何在oracle

时间:2018-09-06 03:49:04

标签: oracle to-date

考虑table1table2

table1的{​​{1}}的值为Column1

'some_string Date: 00:30 05/16/2018 '的{​​{1}}的值为table2

现在我需要同时更新Column2'some_string Date: 07-JUN-2018 ',其中要求首先从给定的字符串值中找到日期,然后将该日期转换为格式'HH24:MI:ss MM / DD / YYYY '

在这里,问题是需要在不同的服务器上更新值,其中字符串值的日期可能具有不同的格式。我试图写上面的查询,但它不起作用。

table1

1 个答案:

答案 0 :(得分:1)

SQL Fiddle

Oracle 11g R2架构设置

CREATE TABLE table1 ( column1 VARCHAR2(100) );

INSERT INTO table1 VALUES ( 'some_string Date: 00:30 05/16/2018 ' );

查询1

MERGE INTO table1 dst
USING (
  WITH split ( rid, prefix, dt ) AS (
    SELECT ROWID,
           SUBSTR( column1, 1, INSTR( column1, 'Date: ' ) + 5 ),
           SUBSTR( column1, INSTR( column1, 'Date: ' ) + 6 )
    FROM   table1
    WHERE  INSTR( column1, 'Date: ' ) > 0
  ),
  converted_dts ( rid, prefix, dt ) AS (
    SELECT rid,
           prefix,
           CASE
           WHEN REGEXP_LIKE( dt, '^\s*\d?\d:\d\d \d?\d([/-])\d?\d\1\d{1,4}\s*$' )
           THEN TO_DATE( dt, 'HH24:MI MM/DD/YYYY' )
           WHEN REGEXP_LIKE( dt, '^\s*\d?\d([\-])(JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NO|DEC)\1\d{1-4})\s*%' )
           THEN TO_DATE( dt, 'DD-MON-YYYY' )
           END
    FROM   split
  )
  SELECT rid,
         prefix,
         TO_CHAR( dt, 'HH24:MI:ss MM/DD/YYYY' ) AS dt
  FROM   converted_dts
  WHERE  dt IS NOT NULL
) src
ON ( dst.ROWID = src.RID )
WHEN MATCHED THEN
  UPDATE
  SET column1 = prefix || dt

Results

查询2

SELECT *
FROM   table1

Results

|                               COLUMN1 |
|---------------------------------------|
| some_string Date: 00:30:00 05/16/2018 |