Book Image

SQL Query Design Patterns and Best Practices

By : Steve Hughes, Dennis Neer, Dr. Ram Babu Singh, Shabbir H. Mala, Leslie Andrews, Chi Zhang
5 (1)
Book Image

SQL Query Design Patterns and Best Practices

5 (1)
By: Steve Hughes, Dennis Neer, Dr. Ram Babu Singh, Shabbir H. Mala, Leslie Andrews, Chi Zhang

Overview of this book

SQL has been the de facto standard when interacting with databases for decades and shows no signs of going away. Through the years, report developers or data wranglers have had to learn SQL on the fly to meet the business needs, so if you are someone who needs to write queries, SQL Query Design and Pattern Best Practices is for you. This book will guide you through making efficient SQL queries by reducing set sizes for effective results. You’ll learn how to format your results to make them easier to consume at their destination. From there, the book will take you through solving complex business problems using more advanced techniques, such as common table expressions and window functions, and advance to uncovering issues resulting from security in the underlying dataset. Armed with this knowledge, you’ll have a foundation for building queries and be ready to shift focus to using tools, such as query plans and indexes, to optimize those queries. The book will go over the modern data estate, which includes data lakes and JSON data, and wrap up with a brief on how to use Jupyter notebooks in your SQL journey. By the end of this SQL book, you’ll be able to make efficient SQL queries that will improve your report writing and the overall SQL experience.
Table of Contents (21 chapters)
1
Part 1: Refining Your Queries to Get the Results You Need
6
Part 2: Solving Complex Business and Data Problems in Your Queries
11
Part 3: Optimizing Your Queries to Improve Performance
14
Part 4: Working with Your Data on the Modern Data Platform

Understanding SQL Server security

SQL Server security determines what information is returned to a user who submits a query. It can be applied at the server, database, schema, table, row, or column level. Each authorized user of a database can only view data that they are authorized to see. Often, when two different people run the same query and they get different results, it is because they do not have the same access to the same tables or data.

Security is typically managed by the database administrator (DBA). If you are not getting the results that you were expecting, you may need to contact the DBA to have the access granted to you.

Security for tables and columns is applied through Grant or Deny statements run by the DBA and look like this: GRANT SELECT ON SCHEMA.TABLE or DENY SELECT ON SCHEMA.TABLE.

For column access, it is the same command with the list of columns to allow or deny access to. Here is what they look like:

GRANT SELECT ON SCHEMA.TABLE(COLUMN 1, COLUMN...