mysql date comparision is not working unable to find the issue - mysql

i have a huge data with dates as string.
column name date1
datatype varchar
the stored data is in this format:14-Mar-2016 05:44:38pm
Now I have split only date from this string like this: 14-03-2016
By using this: DATE_FORMAT(STR_TO_DATE(gr.date1, '%d-%M-%Y'),'%d-%m-%Y')
Now I am trying to compare the date with this query:
SELECT * FROM
( SELECT date1,DATE_FORMAT(STR_TO_DATE(date1, '%d-%M-%Y'),'%d-%m-%Y') as dateFormatted
FROM `grabt` ) as mTbl WHERE mTbl.dateFormatted >= '19-01-2016'
AND mTbl.dateFormatted <= '25-01-2016'
but it is not working what could be the possible error.?

The timestamp string 14-Mar-2016 05:44:38pm can be converted to a datetime using the STR_TO_DATE() along with the format string %d-%b-%Y %r. We can then obtain only the date portion by wrapping that with DATE(). Have a look here for a demo to see that this works.
SELECT *
FROM
(
SELECT DATE(STR_TO_DATE(date1, '%d-%b-%Y %r')) AS dateFormatted
FROM grabt
) AS mTbl
WHERE mTbl.dateFormatted BETWEEN '2016-01-19' AND '2016-01-25'
As Gordon already pointed out, you should ideally be using date types not strings for your date calculations. And by the way, use a valid date string when comparing in your WHERE clause. YYYY-MM-DD is a valid format, e.g. 2016-01-19, but 19-01-2016 is not.

Learn to use the right types for columns. Perhaps you are stuck with someone else's really bad decision to store date/times as strings. Perhaps you cannot change that. But, within a query, use the right types!
SELECT mTbl.*,
LEFT(date1, 10) as FormattedDate -- Is this really necessary?
FROM (SELECT date1,
STR_TO_DATE(LEFT(date1, 10), '%d-%M-%Y') as thedate
FROM `grabt`
) mTbl
WHERE mTbl.thedate >= '2016-01-19' AND
mTbl.thedate <= '2016-01-25';
This will do the comparison as dates not as strings.

Related

Select only date form datetime field in where condition

I have stored this kind of format 2022-02-06 18:40:00 in my trans_reminder_date. I want to use only date in where condition but with this condition i am not able to fetch data
$today = date('Y-m-d');
SELECT * FROM sales_detail
WHERE trans_reminder_date = '".$today."'
AND trans_reminder_date != ''
ORDER BY sales_detail_id DESC";
If when your filter parameter is a string:
select * from sales_detail
where cast(trans_reminder_date as date) = cast('2020-03-22' as date)
if you want to use the current date for filtering then MySQL has a function that getting only the current date without time.
select * from sales_detail
where cast(trans_reminder_date as date) = curdate()
On MySQL for converting other types to another, you can use a cast
P.S.
Starting with MySQL 8.0.13 we have now an easiest way to create functional indexes. When you are using cast(updated_at as date) then DB will not use index for column updated_at. You must create a functional index for best performance.
The following query will give you all the result for the current date. By doing this there won't be any need to cast values.
SELECT
*
FROM
sales_detail
WHERE
trans_reminder_date >= curdate()
AND trans_reminder_date < curdate() + INTERVAL '1' DAY
ORDER BY
sales_detail_id DESC;
Using Cast function to change datetime type to date example
Cast(column_name as date)
Or
You using convert function change datetime type to date
CONVERT(column_name, date);
CONVERT(expression, datatype);
OR,
CONVERT(expression USING character_set);
character_set: It specifies the desired character set in which we want to be converted.
Data type : It specifies the desired data type in which we want to be converted.
Expression : It is a specified value going to be converted into another specific datatype.

How to parse time of ISO timestamp in mysql?

How can a ISO datetime String timestamp be correctly parsed to time type column in mysql? I noticed the following:
select CAST('2013-09-05T10:10:02' as time) from mytable limit 1
Result incorrect:
00:20:13
select CAST(CAST('2013-09-05T10:10:02' as datetime) as time) from mytable limit 1
Result correct:
10:10:02
Why do I have to make a double CAST here to get the correct time? And more important: how is time parsing done property?
Because you have a string which you need to first cast it into date format.
If you cast it in time like below:
select CAST('2014-09-05T10:10:02' as time)
00:20:14
select CAST('2015-09-05T10:10:02' as time)
00:20:15
select CAST('2013' as time) --below casting string as time
00:20:13
If you monitor closely its treating it as string and getting year as time.
So you need to cast it datetime first then time.
select CAST(CAST('2013-09-05T10:10:02' as datetime) as time)
Basically when you try to convert something to a time that looks like an integer MySQL treats that as something in the form HHMMSS, so your 2013-09-05T10:10:02 becomes 00:20:13. To convert properly, the value needs to be a MySQL datetime, which you can do via CAST or you can use STR_TO_DATE to convert your date string to a MySQL date, then TIME to extract the time part of it:
SELECT TIME(STR_TO_DATE('2013-09-05T10:10:02', '%Y-%m-%dT%H:%i:%s'))
Output:
10:10:02
Demo on dbfiddle

SQL Where Date is greater than X

I am trying to run the query;
SELECT PO_PurchaseOrderDetail.ItemCodeDesc,
PO_PurchaseOrderDetail.QuantityOrdered,
PO_PurchaseOrderDetail.QuantityReceived,
PO_PurchaseOrderDetail.UnitCost,
PO_PurchaseOrderDetail.JT158_WTSalesOrderNo,
PO_PurchaseOrderDetail.PurchaseOrderNo,
PO_PurchaseOrderHeader.PurchaseName,
PO_PurchaseOrderHeader.PurchaseOrderDate
FROM PO_PurchaseOrderDetail PO_PurchaseOrderDetail, PO_PurchaseOrderHeader PO_PurchaseOrderHeader
WHERE (PO_PurchaseOrderDetail.PurchaseOrderNo=PO_PurchaseOrderHeader.PurchaseOrderNo)
AND ***(PO_PurchaseOrderHeader.PurchaseOrderDate > '2013-12-31')***
ORDER BY PO_PurchaseOrderDetail.JT158_WTSalesOrderNo, PO_PurchaseOrderDetail.PurchaseOrderNo
My problem is, that the date is stored in the YYYY-MM-DD format. I need to only show data after a certain date. So, because 2013-12-31 is a string rather than a number, the operator > doesn't work. Any ideas?
Try to CAST string as DATE in following:
P.S. if PurchaseOrderDate is not DATE datatype you could also CAST It: CAST(PO_PurchaseOrderHeader.PurchaseOrderDate AS DATE)
SELECT PO_PurchaseOrderDetail.ItemCodeDesc,
PO_PurchaseOrderDetail.QuantityOrdered,
PO_PurchaseOrderDetail.QuantityReceived,
PO_PurchaseOrderDetail.UnitCost,
PO_PurchaseOrderDetail.JT158_WTSalesOrderNo,
PO_PurchaseOrderDetail.PurchaseOrderNo,
PO_PurchaseOrderHeader.PurchaseName,
PO_PurchaseOrderHeader.PurchaseOrderDate
FROM PO_PurchaseOrderDetail PO_PurchaseOrderDetail,
PO_PurchaseOrderHeader PO_PurchaseOrderHeader
WHERE PO_PurchaseOrderDetail.PurchaseOrderNo = PO_PurchaseOrderHeader.PurchaseOrderNo AND
PO_PurchaseOrderHeader.PurchaseOrderDate > CAST('2013-12-31' AS DATE)
ORDER BY PO_PurchaseOrderDetail.JT158_WTSalesOrderNo,
PO_PurchaseOrderDetail.PurchaseOrderNo

Compare String with curdate() - Mysql

I plan to make a selection of multiple database tables.
The problem is that I want the current date is equal to current date, only that it is of type varchar, I can't make a direct comparison with the CURDATE () ... Is there any way to compare the current date with the String type?
Code:
select records.date , records.hour, records.Temp, records.Hum, sensors.idSensor, sensors.idLocalization
from records, sensors
where records.idSensor=sensors.idSensor
and records.date = curdade() // Here is where I wanted to make the comparison date
order by records.date desc;
------------------EDIT (Solved)--------------------------
Thank you all for your help.
I switched CURDATE by curdade.
He made the comparison correctly.
Convert the curdate() to a string of the appropriate format. Something like:
select r.date, r.hour, r.Temp, r.Hum, s.idSensor, s.idLocalization
from records r join
sensors s
on r.idSensor = s.idSensor
where r.date = date_format(curdate(), '%Y-%m-%d') // Here is where I wanted to make the comparison date
order by r.date desc;
You need to use the appropriate format for your date column. I just used the "right" format, the ISO standard date format that is the best to use when representing a date as a string. You can read about the formats in the documentation. And, it is better to turn the current date into the right format than to convert the string to a date. By putting the function on the "constant" part of the comparison, MySQL can still take advantage of an index on date.
Try this. It may work. But this is a date-to-date data type comparison, not a string-to-string comparison.
select STR_TO_DATE(records.date, '%Y-%m-%d') AS date , records.hour, records.Temp, records.Hum, sensors.idSensor, sensors.idLocalization
from records, sensors
where records.idSensor=sensors.idSensor
and date = curdate() // Here is where I wanted to make the comparison date
order by date desc;

Mysql Select with Dates and maybe Case when

im having a problem where i cant think of a solution, maybe im having a bad table-structure or i just dont know enough about mysql select commands to think of a good solution. Maybe you can help me out:
So i got a table that has a Column with the Date-format (yyyy-mm-dd) i wanted to select all upcoming dates so i did:
SELECT * WHERE date >= now.
This worked kinda well but i also got "dates" where only the year is entered (2014-00-00) i also wanted to select these but "now" is already bigger so i made another column with the year only and if the month, date or both arent known i will use 0000-00-00 and the Column "year" now i could select like this:
SELECT * WHERE date >= now AND year >=now(year)
Now all entrys with 0000-00-00 wont be selected. If i use OR the entrys from last year will be shown.
So thats my problem, is there any way i can change my table so i can have entries with only the year or only year and month and of course all together? I already considered get rid of the date-format and use simple INT with seperated columns for year, month and date. But i think i will have the same problem.
Sometimes i just want to do a capsuled select like
SELECT *
WHERE (date >= now AND year >= now(year))
OR date == "0000-00-00" (i know that this doesnt work)
If I understood your problem correctly, you could use this request:
WHERE (date >= now OR year > now(year))
There is probably a simpler way though, that would preserve your design, like initializing at January 1st (01-01) instead of 00-00
I think you can use this code:
$_SESSION['month'] = //set here your selected month
$_SESSION['year'] = //set here your selected year
SELECT * FROM table WHERE DATEPART(m,date) >= '".$_SESSION['month']."' AND DATEPART(yyyy,year) >= '".$_SESSION['year']."' AND date <> '0000-00-00'
Change your table structure format. Actually just allow for that field to have null value when not entered. By default it will be null then. You shouldn't be storing 0000-00-00 as a value for Date type field. I would rather leave it as null , or as suggested in some of previous answers, initialize it with some other date. It would be much easier to manipulate with database then.
the problem is that half of you write is not MySQL and your database schema is terrible...
You have the following problems:
column data date does not have the date data type.
To fix it, you need to add a cast to the select statement eg. cast(datecolumn as date)
select * from table where cast(datecolumn as date) >= '2014-01-10';
the way to use now date is using the now function.
select now(), date(now());
result> 2014-01-10 11:11:36, 2014-01-10
select * from table where cast(datecolumn as date) >= date(now());
Because your datecolumn is not a date (2014-00-00 is not a valid date), you need to use string manipulation to extract the year.
select substring('2014-01-01', 1,4)
result> 2014
select * from table where substring(datecolumn, 1,4) = year(now());
The comparassion operator is = and not ==
the select statement syntax looks like this (pay attention because you are missing the table in your statement)
select * from [Table] where [column] = condition ...
You probably need or instead of ands, therefore your query should look like this:
select * from FooTable where
cast(datecolumn as date) >= date(now())
or substring(datecolumn, 1,4) >= year(now())
or datecolumn = '0000-00-00'
You should use something like phpmyAdmin or mySQL workbench to test your sql queries before try to use them on php, java or whatever is your programing language.