Formatting number to add leading zeros - SQL Server

Formatting numbers to add leading zeros can be done in SQL Server. It is just simple. Lets create a new table and see how it works:

CREATE TABLE Numbers(Num INT);

Table Created.

Lets insert few values and see:

    INSERT Numbers VALUES('8');

    INSERT Numbers VALUES('9');

    INSERT Numbers VALUES('10');

    INSERT Numbers VALUES('11');

    INSERT Numbers VALUES('12');

SELECT * FROM Numbers;

1 row(s) affected.
1 row(s) affected.
1 row(s) affected.
1 row(s) affected.
1 row(s) affected.

Now we can see how the numbers are formatted with 4 digits, if it has less than 4 digits it will add leading zeros.
Data:

SELECT * FROM Numbers;


Num

8
9
10
11
12

5 row(s) affected.

Formatting:
SELECT RIGHT('0000'+ CONVERT(VARCHAR,Num),4) AS NUM FROM Numbers;

Num

0008

0009

0010

0011

0012

5 row(s) affected.

Read More

SQL SERVER – DATEDIFF – Accuracy of Various Dateparts

In SQL statement below the time difference between two given dates is 3 sec, but when checked in terms of Min it says 1 Min (whereas the actual min is 0.05Min)

SELECT DATEDIFF(MI,'2011-10-14 02:18:58' , '2011-10-14 02:19:01') ASMIN_DIFF




Is this is a BUG in SQL Server ?”

Answer is NO.

It is not a bug; it is a feature that works like that. Let us understand that in a bit more detail. When you instruct SQL Server to find the time difference in minutes, it just looks at the minute section only and completely ignores hour, second, millisecond, etc. So in terms of difference in minutes, it is indeed 1.

The following will also clear how DATEDIFF works:

SELECT DATEDIFF(YEAR,'2011-12-31 23:59:59' , '2012-01-01 00:00:00') ASYEAR_DIFF

The difference between the above dates is just 1 second, but in terms of year difference it shows 1.

If you want to have accuracy in seconds, you need to use a different approach. In the first example, the accurate method is to find the number of seconds first and then divide it by 60 to convert it to minutes.

SELECT DATEDIFF(second,'2011-10-14 02:18:58' , '2011-10-14 02:19:01')/60.0 AS MIN_DIFF

Even though the concept is very simple it is always a good idea to refresh it. 

Read More