This article is meant to be some kind of a tutorial. After going through it, it should be clearer to you how to create Power Bi report like this on your own. Following this, you can create basically any report you want – company operation report (timesheets, wages, investments), financial analytics (balance sheet, income statement,… Read More »
We distinguish two types of commands with data deleting purpose – SQL commands DELETE and TRUNCATE. Each is suitable for different situations. It is good to know them both and be able to choose the right one in a specific situation. DELETE Syntax (First Command is Optional): DELETE FROM dbo.Table WHERE <Condition>; or DELETE dbo.Table WHERE… Read More »
Were you ever creating a report and did not find a feature in your Power BI Desktop that would enable you to visualize data according to your needs? What are Power BI Custom Visuals? Custom Power BI visuals were created by members of power BI community – programmers, users, and fans of this wonderful tool.… Read More »
Creating a table in the SQL Server database is a basic skill. While creating it using SQL command CREATE TABLE we define: Name of the table together with database definition and scheme List of the columns with appropriate data types, constraints and definition if the column can be empty (NULL vs. NOT NULL) Table can… Read More »
ISNULL and COALESCE are functions used for work with null values (NULL). Both functions return first value out of previously defined entry parameters. There are also some differences between both functions. ISNULL Syntax: SELECT ISNULL(<Column>, <Column Replacement – other column or logic>) FROM dbo.Table COALESCE Syntax: SELECT COALESCE(<Column>, <Column Replacement – other column or logic… Read More »
Views have definitely their place in databases and data warehouses. We are talking about objects which are good to use since they do not contain data (do not take up place in storage). They consist only of table query. More complex views can be more expensive for logical operations mostly with complicated queries with multiple… Read More »
UPDATE Statement is used in SQL to change existing records in a table. This way, we can change one record, multiple records or all of them. Condition based on which are records restricted is placed in WHERE clause. Syntaxe – 3 Ways of UPDATE Usage A) Simple form: Change of the values in certain column… Read More »
This mini-article is intended for beginners. We will take a closer look at how to write a simple T-SQL script, and I will also explain basic SQL commands. We will assemble the individual parts of the script step by step and explain their purpose as we proceed. Let’s dive into SQL basics in the following… Read More »
T-SQL TRUNCATE command deletes all records in the table. Apart from DELETE (more in article SQL DELETE) command, there is no possibility to filter which record to delete. It is all or nothing. Truncate is on the other hand much faster compared to DELETE since it writes less into transaction log. SQL TRUNCATE command Syntax… Read More »
SQL MERGE command is an advanced way of comparing data in two tables (Source and Destination). We compare records and based on match (or difference) we execute UPDATE, INSERT or DELETE according to the result of the table comparison. We will use this mainly with data sync between objects/systems or with ETL processes in environments… Read More »