T-SQL

Timothy Smith
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CTEs in SQL Server; Using Common Table Expressions To Solve Rebasing an Identifier Column

January 31, 2019 by

Since we know that the SQL CTE (common table expression) offers us a tool to group and order data in SQL Server, we will see an applied example of using common table expressions to solve the business challenge of re-basing identifier columns. We can think of the business problem like the following: we have a table of foods that we sell with a unique identifier integer associated with the food. As we sell new foods, we insert the food in our list. After a few years, we observe that many of our queries involve the foods grouped alphabetically. However, our food list is just a list of foods that we add to as needed without any grouping. Rather than re-group or re-order through queries using a SQL CTE or subquery, we want to permanently update the identifier.

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Esat Erkec

SQL Convert Function

January 29, 2019 by

In this article, we will discuss and learn basics and all details about SQL Server data type converting operations and also we will review the SQL CONVERT and TRY_CONVERT built-in functions with various samples. At first, we will explain and clarify syntax of the SQL CONVERT function and then we will learn how can we make data converting process numerical and date/time data types to character data.

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Timothy Smith

Inserts and Updates with CTEs in SQL Server (Common Table Expressions)

January 28, 2019 by

In CTEs in SQL Server; Querying Common Table Expressions the first article of this series, we looked at creating common table expressions for select statements to help us organize data. This can be useful in aggregates, partition-based selections from within data, or for calculations where ordering data within groups can help us. We also saw that we weren’t required to explicitly create a table an insert data, but we did have to ensure that we had names for each of the columns along with the names being unique. Now, we’ll use our select statements for inserts and updates.

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Timothy Smith

CTEs in SQL Server; Querying Common Table Expressions

January 25, 2019 by

Common table expressions (CTEs) in SQL Server provide us with a tool that allows us to design and organize queries in ways that may allow faster development, troubleshooting, and improve performance. In the first part of this series, we’ll look at querying against these with a practice data set. From examples of wrapped query checks to organization of data to multiple structured queries, we’ll see how many options we have with this tool and where it may be useful when we query data.

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Timothy Smith

T-SQL’s Native Bulk Insert Basics

January 8, 2019 by

From troubleshooting many data flow applications designed by others, I’ve seen a common pattern of over complexity with many designs. Putting aside possible risks by introducing too much complexity, troubleshooting these designs often involves opening many different applications – from a notepad file, to SSIS, to SQL Server Management Studio, to a script tool, etc. It may sound like many of these are doing a hundred steps, yet many times, they’re simply importing data from a file, or calling five stored procedures and then a file task of moving a file. This complexity is often unnecessary, as is opening many different tools when we can use a few tools and solve issues faster.

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Sifiso W. Ndlovu

An MDS Driven Approach to a Turnaround Time Calculation in SQL Server

November 30, 2018 by

One calculation that you are almost guaranteed to have to produce in your career as a T-SQL developer relates to the calculation of a turnaround time. This is often a key KPI for measuring the performance of both individuals and teams, particularly when the business operates within a service-oriented sector i.e. customer support, transportation, healthcare etc. Turnaround time calculation does not only refer to business metrics rather any activity (i.e. ordering a pizza) with a recorded start and an end time can have its own turnaround time calculated. In this article we evaluate different options for calculating a turnaround time including using DATEDIFF function, creating your own user-defined function (UDF) as well as an integration with SQL Server Master Data Services.

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Bojan Petrovic

SQL index overview and strategy

November 27, 2018 by

A SQL index is used to retrieve data from a database very fast. Indexing a table or view is, without a doubt, one of the best ways to improve the performance of queries and applications.

A SQL index is a quick lookup table for finding records users need to search frequently. An index is small, fast, and optimized for quick lookups. It is very useful for connecting the relational tables and searching large tables.

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Prashanth Jayaram

Overview of the SQL CAST and SQL CONVERT functions in SQL Server

November 16, 2018 by

This article is an effort to discuss SQL Cast and SQL Convert functions as a follow-up to previous articles, in which we’ve discussed several SQL tips such as SQL Date, SQL Coalesce, SQL Union, SQL Join, SQL Like, SQL String etc.

Sometimes we need to convert data between different SQL data types. In addition to working with data, there are some built-in functions can be used to convert the data. So let’s take a closer look at the SQL conversion functions SQL CAST and SQL CONVERT in detail.

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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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