In some scenarios like ETL or load data into a DB, we need to insert the data into a staging table, where all the columns are String data type and on the next step to cleanse and manipulate the data. I heard a discussion about the data type of the […]
T-SQL
37 posts
In a real world scenario, we can sale in our online store on standard or discounted prices. In this exercise we use three tables to demonstrate the zig-zag JOIN:
I am very happy to announce that my first book, dedicated to Microsoft SQL Server from the Learn Intuitively series is now on KickStarter.
When we write a DML query that is using JOINed tables as data source, first we need to understand the way SQL Server is manipulating the data. The clauses in the DML query statement are ordered as follows: SELECT FROM… JOIN WHERE GROUP BY HAVING ORDER BY Behind the scene […]
When we create dynamic SQL code, we can add the parameters in two ways: Concatenate them into the dynamic code with + Use sp_executesql
In some situations a scheduled shrink of the log files is needed to release disk space. The script bellow can be scheduled in SQL Server Agent Job.
Let’s say that we have a SP with predefined parameters, i.e. @Parameter1 can hold values 1, 2 or 3; @Parameter2 can hold values of A, B, C or D and so on. This script creates all the possible combinations for the parameters of the SP and executes the SP as many times […]
Very often we make changes to the design of an underlying objects, used by views. After we do this, we need to refresh the views to apply the changes. In this example we will: 1. Create View 2. Change the design of an underlying object 3. Refresh all the views […]
I built a function for reporting purposes that shows the duration in hh:mm:ss between two datetime columns. It can be used in a reporting tool to show the data in a log. The max difference in DATEDIFF() is 68 years. Quick and extended calculation (every year is a leap year): 68 years […]