I have DB Update query, I want to update offer_end_dt to a particular date
UPDATE offer SET offer_end_dt = '2020-10-30 00:00:00',
last_update_user_nm = 'testUser',
last_update_tmst = now()
WHERE offer_end_dt LIKE '2020-05-31%';
In above query I have used LIKE because I am not sure about the time.
I ran this query on my test db where I have less record but now I want to run this query on Production DB where we have almost Hundred thousand record.
Is there any way to increase performance of this query? Can I use USE INDEX here? How?
I am using MariaDb.
Assuming that offer_end is a datetime (which it should be), you should do date comparisons:
WHERE offer_end_dt >= '2020-05-31' and offer_end_dt < '2020-06-01';
Have INDEX(offer_end_dt) and do
WHERE offer_end_dt >= '2020-05-31'
AND offer_end_dt < '2020-05-31' + INTERVAL 1 DAY
(With this pattern, there is no need to worry about end-of-month or year, nor leap-year.)
Related
So, i´m trying to select rows between two dates.
In db, the dates also have time.
Therefor i need to use LIKE.
SQL
$query = "SELECT * FROM table WHERE date >= LIKE :selectedDateFrom AND <= LIKE :selectedDateTo";
$query_params = array(':selectedDateFrom' => $selectedDateFrom.="%", ':selectedDateTo' => $selectedDateTo.="%");
This one returns error!
How should it look like?
In db, the dates also have time.
Therefor i need to use LIKE.
No, you don't.
To select all date/times where the date component is between (from) and (to), inclusive, you can write it as
SELECT *
FROM table
WHERE date >= :selectedDateFrom
AND date < :selectedDateToPlusOne
(Note the < instead of <=, and set the second parameter to one day after the last day you want to include in your results.) This works even when the column includes times.
you can't use like with dates in SQL
SO use this:
$query = "SELECT * FROM table WHERE date >= :selectedDateFrom AND date <= :selectedDateTo";
You'd strip the time part from a datetime with DATE().
SELECT *
FROM mytable
WHERE date(mydate) >= :selectedDateFrom
AND date(mydate) <= :selectedDateTo;
Or with BETWEEN for better readability:
SELECT *
FROM mytable
WHERE date(mydate) BETWEEN :selectedDateFrom AND :selectedDateTo;
I am looking for a way to select a whole days worth of data from a where statement. Timestamp is in unix time such as (1406045122). I want to select the today's date of unix time range and find all the food that has been added in today. Thank in advance. This is the code I wrote. I'm not sure what I should put in the ( ????? ) part. I know it has to do with 60*60*24=86400 secs per day but I'm not too sure how I can implement this.
Select timestamp,food from table1 where timestamp = ( ????? );
Select timestamp,food
FROM table1
WHERE timestamp > :ts
AND timestamp <= (:ts + 86400);
replace :ts with the starting timstamp and you'll filter a whole day's worth of data
edit
This select query would give you the current timestamp (there may be more efficient ones, i don't work with sqlite often)
select strftime("%s", current_timestamp);
You can find more info about them here: http://www.tutorialspoint.com/sqlite/sqlite_date_time.htm
Using the strftime() function, combined with the date() function we can write this following query which will not need any manual editing. It will return the records filtered on timestamp > start of today & timestamp <= end of today.
Select timestamp,food
FROM table1
WHERE timestamp > strftime("%s", date(current_timestamp))
AND timestamp <= (strftime("%s", date(current_timestamp)) + 86400);
Your mileage will likely depend on your version of SQL but for example on MySQL you can specify a search as being BETWEEN two dates, which is taken conventionally to mean midnight on each. So
SELECT * FROM FOO WHERE T BETWEEN '2014-07-01' AND '2014-07-02';
selects anything with a timestamp anywhere on 1st July 2014. If you want to make it readable you could even use the ADDDATE function. So you could do something like
SET #mydate = DATE(T);
SELECT * FROM FOO WHERE T BETWEEN #mydate AND ADDDATE(#mydate, 1);
The first line should truncate your timestamp to be 00:00:00. The second line should SELECT only records from that date.
Suppose I have a date 2010-07-29. Now I would like to check the result of one day ahead. how to do that
For example,
SELECT *
from table
where date = date("2010-07-29")
How to do one day before without changing the string "2010-07-29"?
I searched and get some suggestion from web and I tried
SELECT *
from table
where date = (date("2010-07-29") - 1 Day)
but failed.
MySQL
SELECT *
FROM TABLE t
WHERE t.date BETWEEN DATE_SUB('2010-07-29', INTERVAL 1 DAY)
AND '2010-07-29'
Change DATE_SUB to DATE_ADD if you want to add a day (and reverse the BETWEEN parameters).
SQL Server
SELECT *
FROM TABLE t
WHERE t.date BETWEEN DATEADD(dd, -1, '2010-07-29')
AND '2010-07-29'
Oracle
SELECT *
FROM TABLE t
WHERE t.date BETWEEN TO_DATE('2010-07-29', 'YYYY-MM-DD') - 1
AND TO_DATE('2010-07-29', 'YYYY-MM-DD')
I used BETWEEN because the date column is likely DATETIME (on MySQL & SQL Server, vs DATE on Oracle), which includes the time portion so equals means the value has to equal exactly. These queries give you the span of a day.
If you're using Oracle, you can use the + and - operators to add a number of days to a date.
http://psoug.org/reference/date_func.html
Example:
SELECT SYSDATE + 1 FROM dual;
Will yield tomorrow's date.
If you're not using Oracle, please tell use what you ARE using so we can give better answers. This sort of thing depends on the database you are using. It will NOT be the same across different databases.
Depends of the DateTime Functions available on the RDBMS
For Mysql you can try:
mysql> SELECT DATE_ADD('1997-12-31',
-> INTERVAL 1 DAY);
mysql> SELECT DATE_SUB('1998-01-02', INTERVAL 31 DAY);
-> '1997-12-02'
If youre using MSSQL, you're looking for DateAdd() I'm a little fuzzy on the syntax, but its something like:
Select * //not really, call out your columns
From [table]
Where date = DateAdd(dd, -1, "2010-07-29",)
Edit: This syntax should be correct: it has been updated in response to a comment.
I may have the specific parameters in the wrong order, but that should get you there.
In PL SQL : select sysdate+1 from dual;
How can I select 12/20/2008 in where clause of sql?
The server is SQL server 2005.
select * from tblErrorLog
where errorDate = '12/20/2008'
WHERE datetime_column >= '20081220 00:00:00.000'
AND datetime_column < '20081221 00:00:00.000'
First of all, I'd recommend using the ISO-8601 standard format for date/time - it works regardless of the language and regional settings on your SQL Server. ISO-8601 is the YYYYMMDD format - no spaces, no dashes - just the data:
select * from tblErrorLog
where errorDate = '20081220'
Second of all, you need to be aware that SQL Server 2005 DATETIME always includes a time. If you check for exact match with just the date part, you'll get only rows that match with a time of 0:00:00 - nothing else.
You can either use any of the recommend range queries mentioned, or in SQL Server 2008, you could use the DATE only date time - or you could do a check something like:
select * from tblErrorLog
where DAY(errorDate) = 20 AND MONTH(errorDate) = 12 AND YEAR(errorDate) = 2008
Whichever works best for you.
If you need to do this query often, you could either try to normalize the DATETIME to include only the date, or you could add computed columns for DAY, MONTH and YEAR:
ALTER TABLE tblErrorLog
ADD ErrorDay AS DAY(ErrorDate) PERSISTED
ALTER TABLE tblErrorLog
ADD ErrorMonth AS MONTH(ErrorDate) PERSISTED
ALTER TABLE tblErrorLog
ADD ErrorYear AS YEAR(ErrorDate) PERSISTED
and then you could query more easily:
select * from tblErrorLog
where ErrorMonth = 5 AND ErrorYear = 2009
and so forth. Since those fields are computed and PERSISTED, they're always up to date and always current, and since they're peristed, you can even index them if needed.
You don't say which database you are using but in MS SQL Server it would be
WHERE DateField = {d '2008-12-20'}
If it is a timestamp field then you'll need a range:
WHERE DateField BETWEEN {ts '2008-12-20 00:00:00'} AND {ts '2008-12-20 23:59:59'}
Assuming we're talking SQL Server DateTime
Note: BETWEEN includes both ends of the range, so technically this pattern will be wrong:
errorDate BETWEEN '12/20/2008' AND '12/21/2008'
My preferred method for a time range like that is:
'20081220' <= errorDate AND errordate < '20081221'
Works with common indexes (range scan, SARGable, functionless) and correctly clips off midnight of the next day, without relying on SQL Server's time granularity (e.g. 23:59:59.997)
Use a convert function to get all entries for a particular day.
Select * from tblErrorLog where convert(date,errorDate,101) = '12/20/2008'
See CAST and CONVERT for more info
select * from tblErrorLog
where errorDate BETWEEN '12/20/2008' AND DATEADD(DAY, 1, '12/20/2008')
Use below query for clear understanding
/****** Script for SelectTopNRows command from SSMS ******/
SELECT *
FROM [dbo].[PublishedInfo]
where PublishedDate >= '2022-02-14T11:31:16.5299166+00:00'
If I have a datetime field, how do I get just records created later than a certain time, ignoring the date altogether?
It's a logging table, it tells when people are connecting and doing something in our application. I want to find out how often people are on later than 5pm.
(Sorry - it is SQL Server. But this could be useful for other people for other databases)
For SQL Server:
select * from myTable where datepart(hh, myDateField) > 17
See http://msdn.microsoft.com/en-us/library/aa258265(SQL.80).aspx.
What database system are you using? Date/time functions vary widely.
For Oracle, you could say
SELECT * FROM TABLE
WHERE TO_CHAR(THE_DATE, 'HH24:MI:SS') BETWEEN '17:00:00' AND '23:59:59';
Also, you probably need to roll-over into the next day and also select times between midnight and, say, 6am.
In MySQL, this would be
where time(datetimefield) > '17:00:00'
The best thing I can think would be: don't use a DateTime field; well, you could use a lot of DATEADD/DATEPART etc, but it will be slow if you have a lot of data, as it can't really use an index here. Your DB may offer a suitable type natively - such as the TIME type in SQL Server 2008 - but you could just as easily store the time offset in minutes (for example).
For MSSQL use the CONVERT method:
DECLARE #TempDate datetime = '1/2/2016 6:28:03 AM'
SELECT
#TempDate as PassedInDate,
CASE
WHEN CONVERT(nvarchar(30), #TempDate, 108) < '06:30:00' then 'Before 6:30am'
ELSE 'On or after 6:30am'
END,
CASE
WHEN CONVERT(nvarchar(30), #TempDate, 108) >= '10:30:00' then 'On or after 10:30am'
ELSE 'Before 10:30am'
END
Another Oracle method for simple situations:
select ...
from ...
where EXTRACT(HOUR FROM my_date) >= 17
/
http://download.oracle.com/docs/cd/B19306_01/server.102/b14200/functions050.htm#SQLRF00639
Tricky for some questions though, like all records with the time between 15:03:21 and 15:25:45. I'd also use the TO_CHAR method there.
In Informix, assuming that you use a DATETIME YEAR TO SECOND field to hold the full date, you'd write:
WHERE EXTEND(dt_column, HOUR TO SECOND) > DATETIME(17:00:00) HOUR TO SECOND
'EXTEND' can indeed contract the set of fields (as well as extend it, as the name suggests).
As Thilo noted, this is an area of extreme variability between DBMS (and Informix is certainly one of the variant ones).
Ok, I've got it.
select myfield1,
myfield2,
mydatefield
from mytable
where datename(hour, mydatefield) > 17
This will get me records with a mydatefield with a time later than 5pm.