The Oracle database queries the year, month, day, and 24 hours (Instance) of the day in the time range according to the time range, and the oracle database

The Oracle database queries the year, month, day, and 24 hours (Instance) of the day in the time range according to the time range, and the oracle database
Year in the query time range

SELECT    TO_CHAR (        ADD_MONTHS (            TO_DATE ('2013', 'yyyy'),            (ROWNUM - 1) * 12        ),        'yyyy'    ) AS yearsFROM    DUAL CONNECT BY ROWNUM <= MONTHS_BETWEEN (        TO_DATE ('2018', 'yyyy'),        TO_DATE ('2013', 'yyyy')    ) / 12 + 1

Query the corresponding month in the time range

SELECT    TO_CHAR (        ADD_MONTHS (            TO_DATE ('2017-10', 'yyyy-MM'),            ROWNUM - 1        ),        'yyyy-MM'    ) AS monthsFROM    DUAL CONNECT BY ROWNUM <= MONTHS_BETWEEN (        TO_DATE ('2018-04', 'yyyy-MM'),        TO_DATE ('2017-10', 'yyyy-MM')    ) + 1

Query the date corresponding to the time range

SELECT    TO_CHAR (        TO_DATE ('2017-11-01', 'yyyy-MM-dd') + ROWNUM - 1,        'yyyy-MM-dd'    ) AS TIMEFROM    DUAL CONNECT BY ROWNUM <= TRUNC (        TO_DATE ('2017-12-01', 'yyyy-MM-dd') - TO_DATE ('2017-11-01', 'yyyy-MM-dd')    ) + 1

Query the 24 hours of a day

SELECT    TO_CHAR (        TO_DATE ('2017-01-01', 'yyyy-mm-dd') + (ROWNUM - 1) / 24,        'hh24'    ) AS HOURFROM    dual CONNECT BY 24 >= ROWNUM

Of course, the preceding SQL statements are based on the Oracle database and are not suitable for other databases.

Query the year, month, and day in a certain period of time, mainly used to left join other data. Generally speaking, it is more practical to query report data. Next I will write the SQL statements about the 24-hour SQL statement of the SQL server database query time range, namely year, month, day, and day.