T-SQL

Bojan Petrovic

SQL Join introduction and overview

November 15, 2018 by

A SQL Join clause is put within a Select statement and at the end, it’s given a join condition, which tells the database how to fetch your data. The column specified within the join condition must be preceded by a table name if the column name is the same in both tables. When a column is preceded with a table name, it’s known as a qualified column.

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Prashanth Jayaram

SQL date format Overview; DateDiff SQL function, DateAdd SQL function and more

October 31, 2018 by

SQL date format functions like the DateDiff SQL function and DateAdd SQL Function are oft used by DBAs but many of us never took the time to fully understand these extremely useful features. For professionals just getting started with SQL Server, these functions are some of the first to become familiar with. So hopefully this article will have a little something for everyone across the skill spectrum

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Rajendra Gupta
Data truncation error

SQL truncate enhancement: Silent Data truncation in SQL Server 2019

October 31, 2018 by

In this article, we’ll take a look into SQL truncate improvement in SQL Server 2019.

Data inserts and updates are a normal and regular task for the developers and database administrators as well as from the application. The source of the data can be in multiple forms as if direct insert using T-SQL, stored procedures, functions, data import from flat files, SSIS packages etc.

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Prashanth Jayaram

Overview of the SQL Insert statement

October 16, 2018 by

This article on the SQL Insert statement, is part of a series on string manipulation functions, operators and techniques. The previous articles are focused on SQL query techniques, all centered around the task of data preparation and data transformation.

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Prashanth Jayaram

Static and Dynamic SQL Pivot and Unpivot relational operator overview

October 12, 2018 by

In this article, we’ll walk-through the SQL Pivot and SQL Unpivot operators and how they can be useful to transpose SQL Server data. Also, we’ll discuss both static and dynamic ways to use PIVOT and UNPIVOT relational operators that can be used to transform aggregated distinct values as column(s) in the result-set by specifying all the column values in the PIVOT IN clause.

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Prashanth Jayaram

Overview of the SQL Update statement

October 8, 2018 by

In this article, we’ll walk-through the SQL update statement to modify one or more existing rows in the table. 

In order to modify data in a table, we’ll use an Update statement, a DML (data manipulation language) statement. A SQL update statement comes with a SET clause where we define the column-and-value as a pair of items. In addition, you can enforce the conditional clause. In order to limit the number of rows, we’ll need to set up a where clause. The condition is defined in the where clause that identifies what rows to modify in the table.

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Prashanth Jayaram

Overview of the SQL LIKE Operator

October 2, 2018 by

In this article, we are going to learn how to use the SQL LIKE operator, in SQL Server, using regular expressions to find and/or manipulate text. We will start by learning the symbols and basic syntax of using wildcard regular expressions. We will use character sets and repetition expressions to create flexible matching patterns, and along the way, we’ll examine different ways to use the LIKE operator. And then, finally, in the latter part of the section, we will explore some of the most common and most useful regular expression examples.

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Prashanth Jayaram

SQL Join overview and tutorial

September 17, 2018 by

The ability to combine results from related rows from multiple tables is an important part of relational database system design. In SQL Server, this is accomplished with the SQL join clause.  It’s the nature of traditional relational database systems where some table contains information related to other tables with a common key value. Using a SQL join, you can easily perform queries on related data-sets from multiple tables with these shared keys.

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Bojan Petrovic

Querying data using the SQL Case statement

September 12, 2018 by

The Case statement in SQL is mostly used in a case with equality expressions. The SQL Case statement is usually inside of a Select list to alter the output. What it does is evaluates a list of conditions and returns one of the multiple possible result expressions.

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Timothy Smith

Useful T-SQL techniques for development in SQL Server

July 17, 2018 by

When we’re developing solutions, we can sometimes forget useful commands we can use in T-SQL that make it convenient to remove data, eliminate objects, or carefully remove data. We look at three of these commands with a few examples of where we might consider using them in development, or in rare production cases. While they may offer us speed and convenience in some cases, we also look at some situations where they may not be the best tool to use.

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Timothy Smith

SQL Server – using lowest unit of measurement in T-SQL

July 2, 2018 by

A client recently discovered a discrepancy on one of our reports that showed an improvement in performance metrics but was inaccurate. Our reports came from a software tool, which showed the average performance throughout the day. It derived this number from periodic checks and the frequency changed, which affected our report. When we showed an improvement in the metrics on a report, the client showed us that the frequency change may have impacted this, not necessarily any improvement in performance. In situations where we’re measuring values and comparing them to other values, how can we prevent a change in measurement from impacting our reports? Read more »

Nikhilesh Patel

The HashBytes function in T-SQL

May 16, 2018 by

One of the paramount ways to guard data within a database is to utilize database encryption. However, no one encryption solution is perfect for all databases. Which encryption solution you select totally depends on the requirements of your application. Note that more powerful encryption for larger amounts of data requires a healthy amount of CPU. So, be prepared in the event that that introduction of encryption increases the system load.

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