This introduction to JOINs shows INNER, LEFT, RIGHT, FULL and CROSS JOIN with Venn diagrams and real results from two small tables. It also covers finding rows with no match and three traps that catch people. I first wrote it for members of the Gandhinagar SQL Server User Group.
SQL Server emergency? Email pinal@sqlauthority.com with URGENT in the subject line.
System Configuration Checker WMI Error: Fixing SQL Server Setup
Setup stopped with a WMI message before installing anything? Here are the safe repair steps, in order, with a quick check at the end.
SQL SERVER – Interesting Observation of DMV of Active Transactions and DMV of Current Transactions
sys.dm_tran_active_transactions and sys.dm_tran_current_transaction look alike, but one lists active transactions for the instance, the other only your session.
SQL SERVER – Restore or Attach Database Without .NDF or .MDF is Not Possible
Can you restore or attach database files if the .mdf or an .ndf file is missing? In one word, no. Here is why every data file is needed.
Replacing Profiler Traces With Extended Events
Replacing Profiler traces with Extended Events starts with the question, a focused event session, and a bounded target that avoids needless load.
Standard DBA Reports You Can Write in T-SQL
Standard DBA reports can use T-SQL to show backup age, database sizes, job failures, login changes, and errors in one weekly review.
SQL SERVER – Fix Error 9803. Invalid data for type “numeric” – Data Type Mapping
My present article talks about an error that you will encounter when connecting to Oracle database using OPENQUERY. Let us learn about how to fix error 9803.
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Who We Are
Pinal Dave is an SQL Server Performance Tuning Expert and independent consultant with over 24 years of hands-on experience. He holds a Masters of Science degree and numerous database certifications.
Pinal has authored 19 books and 125 Pluralsight courses. To freely share his knowledge and help others build their expertise, Pinal has also written more than 5,800 database tech articles on his blog at https://blog.sqlauthority.com.
Pinal is also a CrossFit Level 1 Trainer (CF-L1) and CrossFit Level 2 Trainer (CF-L2).
Nupur Dave is a social media enthusiast and an independent consultant. She primarily focuses on the database domain, helping clients build short and long-term multi-channel campaigns to drive leads for their sales pipeline.
Shaivi Pinalkumar Dave is a book author and a women’s artistic gymnast.

