I have to convert a column to a date and then compare the month of the column with the current month.
The column looks like this :
Date
0117
0217
0317
..
I know how to convert it but cant compare it.
select date,to_date(date, 'mmyy')
from table
where ????
any ideas?
You can convert the value to a date using to_date():
select to_date(mmyy, 'MMYY')
from t;
Note that I renamed the column mmyy to clarify what it contains.
This returns the first day of the month.
The result of to_date() can then be compared to the current date. For instance, to match the first of date of the month:
where to_date(mmyy, 'MMYY') = trunc(sysdate)
If you want to match everything in the month, just use an appropriate comparison:
where to_char(to_date(mmyy, 'MMYY'), 'YYYY-MM') = to_char(sysdate, 'YYYY-MM')
or, more simply:
where mmyy = to_char(sysdate, 'MMYY')
You can convert the current date to a string and use string comparisons (which would allow you to use an index on your column):
SELECT *
FROM your_table
WHERE your_date_column = TO_CHAR( SYSDATE, 'MMYY' )
or you can convert the column to a date and compare it (which would not use an index on your column but could use a function-based index, if you created one):
SELECT *
FROM your_table
WHERE TO_DATE( your_date_column, 'MMYY' ) = TRUNC( SYSDATE, 'MM' )
Related
I have a table with a date column (DD/MM/YYYY hh:mm:ss) as follows:
02/09/2021 09:50:37
03/09/2021 09:20:27
02/09/2021 14:05:25
03/09/2021 12:50:28
02/09/2021 14:25:26
What's the most efficient way to filter by date?
Note: I tried with
select date
from table
where date = '02/09/2021'
However, this provides results that wrongly lack the time and only contain the date 02/09/2021.
For example, 02/09/2021 09:50:37 would not be returned.
A simple option is
select *
from your_table
where trunc(date_column) = date '2021-09-02'
If there's an index on date_column, it wouldn't be used in that case so performance might suffer so you'll have to either create a function-based index, or use a different where clause:
where date_column >= date '2021-09-02' and date_column < date '2021-03-03'
If you want to return every record that has some date column equal to some date regardless to the time part then you need this:
select date
from table
where trunc(date) = '02/09/2021'
please avoid naming columns date and tables table.
Here is a small demo
Use a date range:
SELECT date_column
FROM table_name
WHERE date_column >= DATE '2021-09-02'
AND date_column < DATE '2021-09-02' + INTERVAL '1' DAY;
This will enable Oracle to use an index on the date_column column.
If you filter using:
TRUNC(date_column) = DATE '2021-09-02' or
TO_CHAR(date_column, 'DD-MM-YYYY') = '02-09-2021'
Then Oracle will not use an index on the date_column and would need a separate function-based index on either TRUNC(date_column) or TO_CHAR(date_column, 'DD-MM-YYYY').
In my select I am using this
(TRUNC(TO_DATE(TIMESTAMP, 'dd.mm.yyyyHH24:mi'))) TIMESTAMP,
to get the following output in a date format: e.g. 22/04/2016
Now I want to add a statement in my WHERE-clause to show only dates in special months, for example only dates which are in MARCH and APRIL
I tried using this:
WHERE (TRUNC(TO_DATE(TIMESTAMP, 'mm'))) in (3,4)
which gives me an error.
Thanks for helping.
Just use EXTRACT() on the timestamp:
WHERE EXTRACT(MONTH FROM timestamp) IN (3, 4)
This would match records from March and April.
In my select I am using this
(TRUNC(TO_DATE(TIMESTAMP, 'dd.mm.yyyyHH24:mi'))) TIMESTAMP,
to get the following output in a date format: e.g. 22/04/2016
TO_DATE takes a string value so your "TIMESTAMP" column will be implicitly converted to a string and then back to a date... which is unnecessary (and relies on the value of the NLS_TIMESTAMP_FORMAT session parameter to format the implicit conversion - which, if changed, will break the query); you can just do:
TRUNC( "TIMESTAMP" ) AS "TIMESTAMP"
If you want to then filter on different months then you can do (as suggested by Tim Biegeleisen):
WHERE EXTRACT( MONTH FROM "TIMESTAMP" ) IN ( 3, 4 )
or if you want a particular year then
WHERE TRUNC( "TIMESTAMP", 'MM' ) IN ( DATE '2016-03-01', DATE '2016-04-01' )
or, so you can use an index on the column:
WHERE "TIMESTAMP" >= DATE '2016-03-01'
AND "TIMESTAMP" < DATE '2016-05-01'
I have a column with DATE datatype in a table.
I am trying to retrieve the column values in YYYYMM format. My select query looks like below
select *
from tablename
where date column = to_char(to_date('12/31/4000','MM/DD/YYYY'),'YYYYMM');
I am getting below exception.
ORA-01847: day of month must be between 1 and last day of month
Appreciate any input on this.
I think the simplest method is:
where to_char(datecolumn, 'YYYYMM') = '400012'
Or, if you prefer:
where to_char(datecolumn, 'YYYYMM') = to_char(to_date('12/31/4000', 'MM/DD/YYYY'), 'YYYYMM');
Syntax-wise, the right hand date (to the right of the equals) is OK. But you are doing a character comparison, not a date comparison.
This works for me in multiple databases:
select to_char (to_date('12/31/4000','MM/DD/YYYY'),'YYYYMM')
from dual;
Even though your column is named DATE_COLUMN, you are comparing based on characters in the query.
So, try this instead - this compares based on dates (NOT a character comparison) and truncates off the hour, minute, ETC. so you are only comparing the DAY:
select * from DATE_TAB
where TRUNC(DATE1, 'DDD') = TRUNC(to_date('12/31/4000','MM/DD/YYYY'),'DDD');
NOTE: The DATE1 field above is a DATE field. If you're DATE_COLUMN is not a DATE field, you must
convert it to a DATE datatype first (using TO_DATE, ETC.)
Assuming that "date_column" is actually a date, and that you have an index on date_column, you can do something like this to return the data quickly (without truncating dates in all rows to do a comparison):
with dat as (
select level as id, sysdate - (level*10) as date_column
from dual
connect by level <= 100
)
select id, date_column
from dat
where date_column between to_date('11/1/2013', 'MM/DD/YYYY') and last_day(to_date('11/2013 23:59:59', 'MM/YYYY HH24:MI:SS'))
Here I just dummy up some data with dates going back a few years. This example picks all rows that have a date in the month of November 2013.
If your date_column's data-type is DATE, then use
select *
from tablename
where TO_CHAR(date_column,'YYYYMM') = to_char (to_date('12/31/4000','MM/DD/YYYY'),'YYYYMM');
If your date_column's data-type is VARCHAR, then use:
select *
from tablename
where date_column = to_char (to_date('12/31/4000','MM/DD/YYYY'),'YYYYMM');
I somehow feel your error is because you have a space between date and column as
"date column". If the field name in the table is "COLUMN", then just removing the word "DATE" from your original query would suffice, as:
select *
from tablename
where column = to_char(to_date('12/31/4000','MM/DD/YYYY'),'YYYYMM');
If your column (YYYYMMDD) is in number format, the simplest way to get YYYYMM would be
select floor(DATE/100)
from tablename;
Im trying to do a query where a TIMESTAMP field is = to a specific date but my query is not working:
The field is type TIMESTAMP(6) which I have only ever worked with DATE / DATETIME fields before. Here is example of a value stored here: 04-OCT-13 12.29.53.000000000 PM
Here is my SELECT statement:
SELECT * FROM SomeTable WHERE timestampField = TO_DATE('2013-10-04','yyyy-mm-dd')
I am retrieving no results and I am assuming it has to do with the fact that its not matching the TIME portion of the timestamp
If you want every record that occurs on a given day then this should work:
SELECT * FROM SomeTable
WHERE timestampField >= TO_TIMESTAMP( '2013-03-04', 'yyyy-mm-dd' )
AND timestampField < TO_TIMESTAMP( '2013-03-05', 'yyyy-mm-dd')
That will be likely to take advantage of an index on timestampField if it exists. Another way would be:
SELECT * FROM SomeTable
WHERE TRUNC(timestampField) = TO_DATE( '2013-03-04', 'yyyy-mm-dd' )
in which case you may want a function-based index on TRUNC(timestampField).
(Note that TRUNC applied to a TIMESTAMP returns a DATE.)
I'm trying to retrieve records from table by knowing the date in column contains date and time.
Suppose I have table called t1 which contains only two column name and date respectively.
The data stored in column date like this 8/3/2010 12:34:20 PM.
I want to retrieve this record by this query for example (note I don't put the time):
Select * From t1 Where date="8/3/2010"
This query give me nothing !
How can I retrieve date by knowing only date without the time?
DATE is a reserved keyword in Oracle, so I'm using column-name your_date instead.
If you have an index on your_date, I would use
WHERE your_date >= TO_DATE('2010-08-03', 'YYYY-MM-DD')
AND your_date < TO_DATE('2010-08-04', 'YYYY-MM-DD')
or BETWEEN:
WHERE your_date BETWEEN TO_DATE('2010-08-03', 'YYYY-MM-DD')
AND TO_DATE('2010-08-03 23:59:59', 'YYYY-MM-DD HH24:MI:SS')
If there is no index or if there are not too many records
WHERE TRUNC(your_date) = TO_DATE('2010-08-03', 'YYYY-MM-DD')
should be sufficient. TRUNC without parameter removes hours, minutes and seconds from a DATE.
If performance really matters, consider putting a Function Based Index on that column:
CREATE INDEX trunc_date_idx ON t1(TRUNC(your_date));
Personally, I usually go with:
select *
from t1
where date between trunc( :somedate ) -- 00:00:00
and trunc( :somedate ) + .99999 -- 23:59:59
Convert your date column to the correct format and compare:
SELECT * From my_table WHERE to_char(my_table.my_date_col,'MM/dd/yyyy') = '8/3/2010'
This part
to_char(my_table.my_date_col,'MM/dd/yyyy')
Will result in string '8/3/2010'
You could use the between function to get all records between 2010-08-03 00:00:00:000 AND 2010-08-03 23:59:59:000
trunc(my_date,'DD') will give you just the date and not the time in Oracle.
Simply use this one:
select * from t1 where to_date(date_column)='8/3/2010'
Try the following way.
Select * from t1 where date(col_name)="8/3/2010"