Convert/get varchar variable to YYYYMM - sql

I have 4 CTE's in this table and the third one contains a DATETIME converted to VARCHAR (with format based on the requirement) as startDate in DD/MM/YYYY format. The last cte does calculations based on the data generated and one of the columns needs to store YYYYMM date based on startDate.
The problem it's getting the year and the month from this converted DATETIME, using convert() it shows this:
IDPER
-------
01/01/ --DD/MM/
These 2 show YYYYMM correctly when startDate isn't converted:
Select *, left(convert(nvarchar(6),new_ini,112),6) as IDPER from table
Select *, convert(nvarchar(6),new_ini,112) as IDPER from table
How could I get YYYYMM format having startDate converted? Or what could be a more smart approach to the requirement

If you have a string in the format DD/MM/YYYY and you want YYYYMM, then use string operations:
select right(new_ini, 4) + substring(new_ini, 4, 2)
You should be storing date values as dates or a related type, not as string. But given that you have already stored this as a string, string operations can do what you need.

My way would be slightly different
SELECT CONVERT(NVARCHAR(6), CONVERT(DATE, new_ini, 103), 112);
Here, I first converted it to date and then formatted to YYYYMMDD and taken 6 chars only

declare #date DATE = GETDATE();
select REPLACE(LEFT(CONVERT(DATE,#date,112),8),'-','') -- 1st approach
select FORMAT(#date,'yyyyMM') --2nd approach

Related

How to convert nvarchar having yyyymm values to date?

I have a table which has a column 'performance month'. The data type of this column is nvarchar(255) and the values are starting from '202001' to '202012'. How can I select last 5 month data from this table?
The simplest way is:
select convert(date, performance_month + '01')
The standard string representation for dates is YYYYMMDD.
For data from the last five months, you can simply use:
performance_month >= format(dateadd(month, -5, getdate()), 'yyyyMM')
That is, don't convert the string to a date. Convert the date to a string -- this helps the optimizer because it can "see" performance_month without the cloud of function calls.

How to split dash-separated values in SQL Server

I have a date saved in an nvarchar type and I want to split the day, month and year into separate nvarchar variables (that means three variables). The date looks as follows: exposure_date ='2018-12-04' and the format is yyyy-dd-mm
any help please?
My whole project is stuck on this.
The "correct" answer here is to fix your datatype. When storing data always choose an appropriate data type for the data you're storing. For a date (with no time part) then the correct datatype is date. if you're storing numerical data, then use a numerical datatype, such as int or decimal. (n)varchar is not a one size fits all datatype and using it to store data that has a data type designed for it is almost always a bad choice. I'm storing the data as an (n)varchar because I need it in a specific format is never an excuse; have your presentation layer handle to display format, not your RDBMS.
The first step, therefore would be to change your string representation yyyy-dd-MM of a date to the ISO format yyyyMMdd by doing:
UPDATE YourTable
SET exposure_date = LEFT(exposure_date,4) + RIGHT(exposure_date,2) + SUBSTRING(exposure_date,6,2);
Now you have a unambiguous representation, you can change the data type of your column without concerns of incorrect implicit casts or error:
ALTER YourTable ALTER COLUMN exposure_date date;
Then, finally, you can treat your data as what it is, a date, and use the DATEPART function:
SELECT DATEPART(YEAR,exposure_date) AS Exposure_Year,
DATEPART(MONTH,exposure_date) AS Exposure_Month,
DATEPART(DAY,exposure_date) AS Exposure_Day
FROM YourTable;
You can also try the following
Declare #myDate date
select #myDate= Cast(substring('2011-29-12', 1, 4)
+ '-' + substring('2011-29-12', 9, 2)
+ '-' + substring('2011-29-12', 6, 2)
as Date) --YYYY-MM-DD
Select #myDate as DateTime,
datename(day,#myDate) as Date,
month(#myDate) as Month,
datename(year,#myDate) as Year,
Datename(weekday,#myDate) as DayName
The output is as shown below
DateTime Date Month Year DayName
--------------------------------------------
2011-29-12 29 12 2011 Thursday
You can find the live demo here
You can try below -
select concat(cast(year(cast('2018-12-04' as date)) as varchar(4)),'-',
cast(month(cast('2018-12-04' as date)) as varchar(2)), '-',
cast(day(cast('2018-12-04' as date)) as varchar(2)))
from tablename
If you have fixed format, then you could use this simple query with substring method:
select substring(dt, 1, 4) + '-' +
substring(dt, 9, 2) + '-' +
substring(dt, 6, 2) [YYYY-MM-DD]
from (values ('2018-31-12')) tbl(dt)
Let's go directly to the main issue, which is you are using the wrong datatype to store dates, you should store them as DATE, the datatypes are there for a reason and you need to choose a proper one for your column.
So, you need to ALTER your table and change the column datatype to DATE instead of NVARCHAR datatype.
ALTER <Table Name Here>
ALTER COLUMN <Column Name Here> DATE;
Then all things will easy, you just run the following query to get the desired output
SELECT YEAR(<Column Name Here>) TheYear,
MONTH(<Column Name Here>) TheMonth,
DAY(<Column Name Here>) TheDay
FROM <Table Name Here>
Which is the right and the best solution.
You can also (if you are not going to alter your table) do as
CREATE TABLE Dates(
StrDate NVARCHAR(10)
);
INSERT INTO Dates VALUES
(N'2018-12-04'),
(N'Invalid');
SELECT LEFT(StrDate, 4) StrYear,
SUBSTRING(StrDate, 6, 2) StrMonth,
RIGHT(StrDate, 2) StrDay
FROM Dates;
OR
SELECT YEAR(StrDate) StrYear,
MONTH(StrDate) StrMonth,
DAY(StrDate) StrDay
FROM (
SELECT TRY_CAST(StrDate AS DATE) StrDate
FROM Dates
)T

date time stored as varchar in sql how to filter on varchar

I am working on a project in which dates and times ar stored as a varchar e.g. "30-11-2017,7:30" first date in dd-mm-yyy format and then time separated with a comma. I am trying to filter on it but it is not working correctly kindly guide me how to filter data on date.
select *
from timetrack
where startDateAndTime >= '30-11-2017,7:30'
In attached image records have been shown. When I apply above query it shows no records
You can easily convert your date to SQL datatype datetime uisng parse function, for example select parse('30-11-2017,7:30' as datetime using 'it-IT').
So, in your case, you can apply this function in where clause, so you can easily apply comparison between dates:
select *
from timetrack
where parse(startDateAndTime as datetime using 'it-IT') >= '2017-11-30 07:30:00.000'
Your format is apparently italian :) But you have to specify your own date in the format convertable to datetime, as I have done in above example.
NOTE: parse is available starting with SQL Management Studio 2012.
Unless you are using ISO date format (yyyy-MM-dd HH:mm:ss or close) applying ordering (which inequalities like greater than or equal use) will not work: the date order is disconnected from the string ordering.
You'll need to parse the date and times into a real date time type and then compare to that (details of this depend on which RDBMS you are using).
If, you want to just filter out the date then you could use convert() function for SQL Server
select *
from timetrack
where startDateAndTime >= convert(date, left(#date, 10), 103)
Else convert it to datetime as follow
select *
from timetrack
where startDateAndTime >= convert(datetime, left(#date, 10)+' ' +
reverse(left(reverse(#date), charindex(',', reverse(#date))-1)), 103)
You need the date in a datetime column, Otherwise you can't filter with your current varchar format of your date.
Without changing the existing columns, this can be achieved by making a computed column and making it persisted to optimize performance.
ALTER TABLE test add CstartDateTime
as convert(datetime, substring(startDateAndTime, 7,4)+ substring(startDateAndTime, 4,2)
+ left(startDateAndTime, 2) +' '+ right(startDateAndTime, 5), 112) persisted
Note: this require all rows in the column contains a valid date with the current format
Firstly, you need to check what is the data that is entered in the 'startDateAndTime' column,then you can convert that varchar into date format
If the data in 'startDateAndTime' column has data like '30-11-2017,07:30', you would then have to convert it into date:
SELECT to_date('30-11-2017,07:30','dd-mm-yyyy,hh:mm') from dual; --check this
--Your query:
SELECT to_date(startDateAndTime ,'dd-mm-yyyy,hh:mm') from timetrack;

finding data lying between a specific date range in sql

I want to find records from my database which lie between any user input date range(say between 10/2/2008 to 26/9/2024). I tried using
SELECT NAME
,TYPE
,COMP_NAME
,BATCH_NO
,SHELF
,MFG_DATE
,EXP_DATE
,QTY
,VAT
,MRP
FROM STOCK_LOCAL
WHERE
convert(VARCHAR(20), EXP_DATE, 103)
BETWEEN convert(VARCHAR(20), #MEDICINEEXP_DATE, 103)
AND convert(VARCHAR(20), #MEDICINEEXPDATE, 103)
but with this query i need to enter perfect date range which is available in my database, it is not giving me data lying in between any date entered.
Thanks in advance
Since it is a poolr designed schema there isnt going to be any decent/Efficient solution for this.
In sql server if you are storing Date or Date & Time data. Use the Data or DATETIME datatypes for your columns.
In your case you are trying to compare a string with passed date. and even when you tried to convert the string (Date) into date datatype you didnt do it correctly.
My suggestion would be Add new columns to your table with Date datatype and update these columns with existing date/string values.
For now you can convert the Date(string) into date datatype using the following code.
DECLARE #MEDICINEEXP_DATE DATE = 'SomeValue1'
DECLARE #MEDICINEEXPDATE DATE = 'SomeValue1'
SELECT query....
FROM TableName
WHERE
CAST(
RIGHT(EXP_DATE, 4)
+SUBSTRING(EXP_DATE,CHARINDEX('/',EXP_DATE)+1,2)
+LEFT(EXP_DATE,2)
AS DATE) >= #MEDICINEEXP_DATE
AND CAST(
RIGHT(EXP_DATE, 4)
+SUBSTRING(EXP_DATE,CHARINDEX('/',EXP_DATE)+1,2)
+LEFT(EXP_DATE,2)
AS DATE) <= #MEDICINEEXPDATE
Note
This solution will get you the expected results but very inefficient method. It will not make use of any indexses on your EXP_DATE Column even if you have a very buffed up index on that column.

Microsoft SQL Server 2008 - Dates

I have a couple of questions in regards to dates in SQL Server.
How do I separate a datetime value "2011-08-10 14:56:17.267" into date and timestamp in two separate columns. Eg. Date "2011-08-10" and timestamp "14:56:17"
I want remove the timestamp from datetime value into "2011-08-10" and still be able to order the data by date (therefore not converted to varchar). Also is there away to change the date value as '10 Aug 2011' and still can sort (not alphabetically but in real date order).
Thank you,
HL
For the first one:
UPDATE atable
SET
DateColumn = CAST(DateTimeColumn AS date),
TimeColumn = CAST(DateTimeColumn AS time)
As for the second one, date display format is something that is unrelated to the date value. You can order the result set by your date column, but in the SELECT clause you can use CONVERT to display the date in the desired format. For example:
SELECT
CONVERT(varchar, DateColumn, 106) AS Date,
…
FROM atable
ORDER BY DateColumn
use CONVERT function with parameters from resource http://www.mssqltips.com/tip.asp?tip=1145
-- simple conversion example:
SELECT CONVERT(VARCHAR(10), GETDATE(), 102) -- for date
SELECT CONVERT(VARCHAR(10), GETDATE(), 8) -- for time