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Comment by baq | Hacker News Reader

To all junior SWEs: read a SQL book over the weekend. You'll end up being the respected DB expert on most calls after literally a few weeks. Most everyone never progresses above a SELECT with a couple JOINs and then complain the DB is slow and need to push work into the backend service where usually the opposite is true.

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Pretty senior developer here (manager now, actually) but I'm realizing that other than college, I haven't really picked up a book on SQL. What would you recommend?

Just go through the W3Schools website first. It's free and you can write queries in the little window to test out things against their simple database.

I usually recommend the table of contents of your RDBMS but just grab whatever you can access quickest which has good reviews.

For SQL Server, I would read through these articles:

https://www.itprotoday.com/sql-server/sql-server-database-en.... Explains role of query plan (can pull either from actual file or from an index(s)) and write-ahead-log (Microsoft gave it the unfortunate name of Transaction Log) for hardening.

https://learn.microsoft.com/en-us/sql/relational-databases/p.... Explains how to use the Query Store to identify poor performing queries.

https://learn.microsoft.com/en-us/sql/relational-databases/s.... Explains that SQL Server handles the problem of two concurrent users attempting to modify the same record at the same time via DEADLOCKS. You want to use Extended Events to troubleshoot deadlocks.

https://learn.microsoft.com/en-us/azure/architecture/pattern.... Explains how CQRS and Event Sourcing architectures can help minimize deadlocks.

https://www.business-case-analysis.com/accounting-cycle.html. I would argue the best architecture to minimize deadlocks is to mimic what accounting systems do. Multiple Clients submit order requests to a batch system that posts/processes them sequentially. Until the central batch system posts, the transaction is pending. Similar to how Amazon accepts your order request instantaneously; but it may take several minutes for your order to be confirmed.

For bonus minutiae, SQL Server has a problem with upserts. Here is the old school and the new way for handling it.

https://sqlperformance.com/2020/09/locking/upsert-anti-patte...

https://learn.microsoft.com/en-us/sql/relational-databases/p...

The second is azure sql only.

Point of clarification: I've used SQL almost my entire development career, with multiple RDBMS engines, I've simply never looked at a book solely on SQL.

Many many years ago, I simply bought the O’Reilley SQL pocket guide, skimmed through it, read the section about Window Functions and that marked the start of a moment in my career that changed my life forever.

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