Tag - query tuning

Finding Table Differences on Nullable Columns Using MySQL Generated Columns

MySQL generated columns

Some time ago, a customer had a performance issue with an internal process. He was comparing, finding, and reporting the rows that were different between two tables. This is simple if you use a LEFT JOIN and an 
IS NULL  comparison over the second table in the WHERE clause, but what if the column could be […]

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Webinar: How to Analyze and Tune MySQL Queries for Better Performance

database query tuning

Please join Percona’s MySQL Database Administrator, Brad Mickel as he presents How to Analyze and Tune MySQL Queries for Better Performance on Thursday, June 21st, 2018, at 10:00 AM PDT (UTC-7) / 1:00 PM EDT (UTC-4).
Register Now
 
Query performance is essential in making any application successful. In order to finely tune your queries you first […]

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EXPLAIN FORMAT=JSON has details for subqueries in HAVING, nested selects and subqueries that update values

Over several previous blog posts, we’ve already discussed what information the 
EXPLAIN FORMAT=JSON output provides for some subqueries. You can review those discussions here and

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Advanced Query Tuning in MySQL 5.6 and MySQL 5.7 Webinar: Q&A

Thank you for attending my July 22 webinar titled “Advanced Query Tuning in MySQL 5.6 and 5.7” (my slides and a replay available here). As promised here is the list of questions and my answers (thank you for your great questions).
Q: Here is the explain example:

MySQL

mysql> explain extended select id, site_id from test_index_id where […]

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Peter Zaitsev hits the road for East Coast MySQL Meetup tour

Percona CEO Peter Zaitsev and Big Data guru Alexander Rubin will be speaking at Meetups along the East Coast next week with stops in Boston (May 11), New York City (May 12), Philadelphia (May 13) and Baltimore (May 14).
Dubbed the “MySQL Whistle-Stop Tour” since they’ll be traveling city to city via Amtrak, Peter will […]

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