Det fungerer perfekt for mig med korrekt brug af TO_DATE og DATE-værdier.
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Brug aldrig TO_DATE på en DATE , Det vil implicit konvertere det til streng og derefter tilbage til dato ved brug af lokalitetsspecifikt NLS-format .
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'01/01/2015'er IKKE en DATO, det er en STRING. Du skal bruge TO_DATE for eksplicit at konvertere den til DATE.
Se, hvad der sker:
SQL> explain plan for select * from dual where to_date(sysdate) > to_date(sysdate -1);
Explained.
SQL> select * from table(dbms_xplan.display);
PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------
Plan hash value: 3752461848
---------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
---------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | 2 | 2 (0)| 00:00:01 |
|* 1 | FILTER | | | | | |
| 2 | TABLE ACCESS FULL| DUAL | 1 | 2 | 2 (0)| 00:00:01 |
---------------------------------------------------------------------------
Predicate Information (identified by operation id):
PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------
---------------------------------------------------
1 - filter(TO_DATE(TO_CHAR([email protected]!))>TO_DATE(TO_CHAR([email protected]!-1)))
14 rows selected.
SQL>
Så det faktiske anvendte filter er filter(TO_DATE(TO_CHAR([email protected] !)) Du vil få forkert output på grund af den implicitte konvertering baseret på lokalitetsspecifikt NLS-format.
Anyway, nu vender jeg tilbage til dit oprindelige spørgsmål.
For eksempel,
Lad os sige, at dine data ser sådan ud:
Opsætning:
SQL> CREATE TABLE t
2 (week_no VARCHAR2(2), long_week_no VARCHAR2(2), week_start_date DATE, week_end_date DATE, mnth VARCHAR2(3), yr VARCHAR2(4))
3 ;
Table created.
SQL>
SQL>
SQL> INSERT ALL
2 INTO t (week_no, long_week_no, week_start_date, week_end_date, mnth, yr)
3 VALUES ('1', '1A', TO_DATE('01/01/2015','DD/MM/YYYY'), TO_DATE('03/01/2015','DD/MM/YYYY'), 'JAN', '2015')
4 INTO t (week_no, long_week_no, week_start_date, week_end_date, mnth, yr)
5 VALUES ('1', '1B', TO_DATE('04/01/2015','DD/MM/YYYY'), TO_DATE('10/01/2015','DD/MM/YYYY'), 'JAN', '2015')
6 INTO t (week_no, long_week_no, week_start_date, week_end_date, mnth, yr)
7 VALUES ('2', '2', TO_DATE('11/01/2015','DD/MM/YYYY'), TO_DATE('17/01/2015','DD/MM/YYYY'), 'JAN', '2015')
8 INTO t (week_no, long_week_no, week_start_date, week_end_date, mnth, yr)
9 VALUES ('3', '3', TO_DATE('18/01/2015','DD/MM/YYYY'), TO_DATE('24/01/2015','DD/MM/YYYY'), 'JAN', '2015')
10 INTO t (week_no, long_week_no, week_start_date, week_end_date, mnth, yr)
11 VALUES ('51', '51', TO_DATE('20/12/2014','DD/MM/YYYY'), TO_DATE('26/12/2015','DD/MM/YYYY'), 'DEC', '2014')
12 SELECT * FROM dual
13 ;
5 rows created.
SQL>
SQL> COMMIT;
Commit complete.
SQL>
Tabel:
SQL> SELECT * FROM t;
WE LO WEEK_STAR WEEK_END_ MNT YR
-- -- --------- --------- --- ----
1 1A 01-JAN-15 03-JAN-15 JAN 2015
1 1B 04-JAN-15 10-JAN-15 JAN 2015
2 2 11-JAN-15 17-JAN-15 JAN 2015
3 3 18-JAN-15 24-JAN-15 JAN 2015
51 51 20-DEC-14 26-DEC-15 DEC 2014
SQL>
Forespørgsel om at filtrere rækkerne baseret på DATE-interval:
SQL> SELECT *
2 FROM t
3 WHERE To_date('15/01/2015', 'DD/MM/YYYY') BETWEEN
4 week_start_date AND
5 week_end_date;
WE LO WEEK_STAR WEEK_END_ MNT YR
-- -- --------- --------- --- ----
2 2 11-JAN-15 17-JAN-15 JAN 2015
51 51 20-DEC-14 26-DEC-15 DEC 2014
SQL>