XML performance tips

Parsing data from XML using XQuery is a routine practice. In order to do this most effectively, little effort is required.

Suppose we need to parse data from the disk file with the following structure:

Use BULK INSERT, if you need to read data from a file:

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Common Examples of SSIS Expressions and Variables

Introduction

This article helps to enrich the functionality of SSIS. It is possible for example to set properties in tasks using expressions and we can assign values and create code to enrich the SSIS functionality.

This article is oriented to SSIS developers who have experience with basic tasks, but are not familiar with variables, scripts to enrich the functionality of the SSIS and to provide dynamic functionality.

This time we will talk about SSIS expressions, variables, and loops in SSIS. We will use expressions to set values in tasks using variables. We will also learn to create Script code in C#.

We will first talk about SSIS expressions and then we will use SSIS with the script task. Finally, we will work with Loop containers and the script task.

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Everything you should know about SQL Server JOINS

The focus of this article is going to be on utilizing JOINs. We will start off by talking a bit about how JOINs are going to happen and why you need to JOIN data. Then we will take a look at the JOIN types that we have available to us and how to use them.

JOIN BASICS

JOINs in TSQL are typically going to be done on the FROM line.

JOIN-Starts-Here

Before we are getting to anything else, the real big question becomes — “Why do we have to do JOINs, and how are we actually going to perform our JOINs?” (more…)

Extended Events for SSAS

Cubes require frequent monitoring since their productivity decreases quite often (slowdowns during query building, processing time increment). To find out the reason of decrease, we need to monitor our system. For this, we use SQL Server Profiler. However, Microsoft is planning to exclude this SQL tracing tool in subsequent versions. The main disadvantage of the tool is resource intensity, and it should be run on a production server carefully, since it may cause a critical system productivity loss.

Thus, Extended Events is a general event-handling system for server systems. This system supports the correlation of data from SQL Server which allows getting SQL Server state events. (more…)

CHECK Constraints in SQL Server

In this article, we will talk about CHECK constraints. We will see how to add CHECK constraints to SQL Server table columns and discuss the pitfalls you may encounter when using this type of SQL Server constraints.

CHECK constraint basics

CHECK constraints are simply conditional statements (predicates that return TRUE or FALSE) that refer to table columns for maintaining data integrity. When one inserts data into a column or several columns in a single row, CHECK constraints come into action. They evaluate the data to be inserted. In case the data does not meet the condition specified in the CHECK constraint, the insertion fails.

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Creating and Accessing In-Memory OLTP Databases and Tables

This is the second article in a series of articles about SQL Server In-Memory OLTP.

The introductory article — SQL Server In-Memory OLTP, briefly introduced the basics of the new Hekaton engine. In this part, we will focus on practice. To be more specific, we will see how to create In-Memory optimized databases and tables, and also, how to assess them with help of T-SQL. (more…)

SQL Server Security Ponderings – Part 1 | DMI – Bobby Returns

Nowadays security and data privacy are in special focus. When I deliver a training, I always refer to a DBA as the “guardian of the data.” There are two aspects of being a guardian.

The first one is integrity. It includes tasks like checking database consistency, creating backups and in case of problems being prepared to fix the database by having well designed, comprehensive DR plan.

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SQL Server In-Memory OLTP: The Basics

This is the first article in a series of articles about In-Memory OLTP. It helps you to understand how the new Hekaton engine works internally. We will focus on details of in-memory optimized tables and indexes. This is the entry-level article, which means you do not need to be an SQL Server expert, however, you do need to have some basic knowledge about the traditional SQL Server engine. (more…)

Deploying Database from Source Control

These days, development teams start new projects from choosing a version control system. There are many benefits of source control systems in coordinating the efforts of the development team. It ensures a complete audit trail of all changes to the code and allows the team to reproduce any specific revision or build. Along with the programming code, databases can and should be placed under source control. In this article, we will have a look at how to deploy a database that is in the remote repository. (more…)