Select where timestamp between date1 and date 2

Question

try a lot of variations but still dont work
this was my last shot, then i come here ask for help
the field DATAHORAS is timestamp
data1 and dat2 will come from a form
To_Date(S.DATAHORAS, 'dd/mm/yyyy hh24:mi:ss')
Between Cast(To_Date(:data1) As TimeStamp) And Cast(To_Date(:data2) As TimeStamp)
thanks in advanced

Answer 1

No. You don't need to. But....
Edit: I was originally using a stupid example using DUAL which was completely misleading - sorry.
Originally I used the example below to show that you don't have to do an explicit conversion.
Things will still work comparing timestamps and dates.
SQL> select systimestamp, sysdate, sysdate+1
  2  from dual
  3  where systimestamp between sysdate and sysdate + 1;
SYSTIMESTAMP                        SYSDATE              SYSDATE+1
09-FEB-10 13.58.35.712017 +00:00    09-FEB-2010 13:58:35 10-FEB-2010 13:58:35But then I added an explain plan to show that implicit conversions were going on:
1  explain plan for
  2  select systimestamp, sysdate, sysdate+1
  3  from dual
  4* where systimestamp between sysdate and sysdate + 1
SQL> /
Explained.
SQL> select * from table(dbms_xplan.display);
PLAN_TABLE_OUTPUT
Plan hash value: 4192335797
| Id  | Operation        | Name              | Rows  | Cost (%CPU)| Time     |
|   0 | SELECT STATEMENT |                   |     1 |     1   (0)| 00:00:01 |
|*  1 |  FILTER          |                   |       |            |          |
|   2 |   INDEX FULL SCAN| SYS_IOT_TOP_57625 |     1 |     1   (0)| 00:00:01 |
Predicate Information (identified by operation id):
PLAN_TABLE_OUTPUT
   1 - filter(SYS_EXTRACT_UTC(SYSTIMESTAMP(6))<=SYS_EXTRACT_UTC(SYSDATE@
              !+1) AND SYS_EXTRACT_UTC(SYSTIMESTAMP(6))>=SYS_EXTRACT_UTC(SYSDATE@!))
15 rows selected.
SQL>However, this example is misleading because it's not the same implicit conversion you get with a proper table with a timestamp column:
SQL> create table t1
  2  (col1 timestamp);
Table created.
SQL> ed
Wrote file afiedt.buf
  1   explain plan
  2   for
  3   select *
  4   from   t1
  5   where col1 between to_date('08-JAN-2010','DD-MON-YYYY')
  6*             and     to_date('09-JAN-2010','DD-MON-YYYY')
SQL> /
Explained.
SQL>
SQL> select * from table(dbms_xplan.display);
PLAN_TABLE_OUTPUT
Plan hash value: 3617692013
| Id  | Operation         | Name | Rows  | Bytes | Cost (%CPU)| Time     |
|   0 | SELECT STATEMENT  |      |     1 |    13 |     2   (0)| 00:00:01 |
|*  1 |  TABLE ACCESS FULL| T1   |     1 |    13 |     2   (0)| 00:00:01 |
Predicate Information (identified by operation id):
PLAN_TABLE_OUTPUT
   1 - filter("COL1">=TIMESTAMP' 2010-01-08 00:00:00' AND
              "COL1"<=TIMESTAMP' 2010-01-09 00:00:00')
Note
   - dynamic sampling used for this statement
18 rows selected.
SQL>Which is really what you want.
It has an implicit conversion on the date parameters and no implicit conversion on the column which would prevent index usage if there were an index.
Interestingly if you explicitly convert the dates to a timestamp, then you can get an extra filter predicate comparing the two parameters:
SQL> explain plan
  2  for
  3  select *
  4  from   t1
  5  where col1 between cast(to_date('08-JAN-2010','DD-MON-YYYY') as timestamp)
  6             and     cast(to_date('09-JAN-2010','DD-MON-YYYY') as timestamp);
Explained.
SQL>
SQL> select * from table(dbms_xplan.display);
PLAN_TABLE_OUTPUT
Plan hash value: 3332582666
| Id  | Operation          | Name | Rows  | Bytes | Cost (%CPU)| Time     |
|   0 | SELECT STATEMENT   |      |     1 |    13 |     2   (0)| 00:00:01 |
|*  1 |  FILTER            |      |       |       |            |          |
|*  2 |   TABLE ACCESS FULL| T1   |     1 |    13 |     2   (0)| 00:00:01 |
Predicate Information (identified by operation id):
PLAN_TABLE_OUTPUT
   1 - filter(CAST(TO_DATE(' 2010-01-08 00:00:00', 'syyyy-mm-dd
              hh24:mi:ss') AS timestamp)<=CAST(TO_DATE(' 2010-01-09 00:00:00',
              'syyyy-mm-dd hh24:mi:ss') AS timestamp))
   2 - filter("COL1">=CAST(TO_DATE(' 2010-01-08 00:00:00', 'syyyy-mm-dd
              hh24:mi:ss') AS timestamp) AND "COL1"<=CAST(TO_DATE(' 2010-01-09
              00:00:00', 'syyyy-mm-dd hh24:mi:ss') AS timestamp))
Note
PLAN_TABLE_OUTPUT
   - dynamic sampling used for this statement
23 rows selected.oracle version 11.1.0.6
Sorry about the mistakes in previous version of this reply.
Edited by: DomBrooks on Feb 9, 2010 2:25 PM