Oracle PL/SQL 上年和上月
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Oracle PL/SQL previous year and month
提问by Pinu
I need to write a script in pl/sql where I get the previous period. Period in the accounting system is defined as YYYYMM i.e for this month the current period would be 201304 and previous months period would be 201303.
我需要在 pl/sql 中编写一个脚本来获取上一期。会计系统中的期间定义为 YYYYMM，即本月当前期间为 201304，上个月期间为 201303。
For one of my functions a period is passed I need to get the previous period. So for example if the period that is passed is 201301 then the query needs to return 201212
对于我的一个功能，过了一段时间我需要获取上一期。例如，如果传递的时间段是 201301 那么查询需要返回 201212
回答by Todd Gibson
SQL only:
仅 SQL：
SELECT TO_CHAR(ADD_MONTHS(TO_DATE(current_period, 'YYYYMM'), -1), 'YYYYMM')
FROM dual;
PL/SQL:
PL/SQL：
previous_period := TO_CHAR(ADD_MONTHS(TO_DATE(current_period, 'YYYYMM'), -1), 'YYYYMM');
