Markus Winand
@winand.at
SQL Renaissance Ambassador. Author, Trainer, Coach. PhD in Common Sense. Creator of http://use-the-index-luke.com and http://modern-sql.com.
Pinned
Markus Winand
@winand.at
· Oct 29
Teaching is about making students reach the same level of understanding as the teacher—but with less mental effort.
This allows students to put their mental efforts into growing beyond their teachers.
This allows students to put their mental efforts into growing beyond their teachers.
Reposted by Markus Winand
Think you know about #SQL performance?
Take this 3-minute indexing quiz by @winand.at
A simple test that 60% fail!
buff.ly/5C4XZ7N
Did you pass? Let us know how you did!
Take this 3-minute indexing quiz by @winand.at
A simple test that 60% fail!
buff.ly/5C4XZ7N
Did you pass? Let us know how you did!
3-Minute Quiz: What do you know about SQL performance?
Just 5 questions to see how much you know about SQL performance. Never make these mistakes again.
buff.ly
February 13, 2026 at 12:02 PM
Think you know about #SQL performance?
Take this 3-minute indexing quiz by @winand.at
A simple test that 60% fail!
buff.ly/5C4XZ7N
Did you pass? Let us know how you did!
Take this 3-minute indexing quiz by @winand.at
A simple test that 60% fail!
buff.ly/5C4XZ7N
Did you pass? Let us know how you did!
Reminder: de.wikipedia.org/wiki/Gilbert...
Gilbert U-238 Atomic Energy Laboratory – Wikipedia
de.wikipedia.org
February 10, 2026 at 4:20 PM
Reminder: de.wikipedia.org/wiki/Gilbert...
Reposted by Markus Winand
Claude's C Compiler vs. GCC | Discussion
CCC vs GCC
A Guide to comparing Claude Code Compiler with GCC
harshanu.space
February 9, 2026 at 5:40 AM
Claude's C Compiler vs. GCC | Discussion
Thanks. It's fixed. I did indeed not understand your first comment ;)
February 6, 2026 at 5:51 AM
Thanks. It's fixed. I did indeed not understand your first comment ;)
SQL Comments, Please!
modern-sql.com/caniuse/comm...
modern-sql.com/caniuse/comm...
Comments Inside SQL Statements
C-style comments work in SQL, with nesting
modern-sql.com
February 5, 2026 at 8:18 AM
SQL Comments, Please!
modern-sql.com/caniuse/comm...
modern-sql.com/caniuse/comm...
Reposted by Markus Winand
What is random, but actually useful, things you wish you had a SQL interface for?
February 4, 2026 at 3:15 PM
What is random, but actually useful, things you wish you had a SQL interface for?
Infinite Recursion Guards
modern-sql.com/caniuse/with...
With recursive is the only SQL construct that is not guaranteed to terminate, eventually. As the DBMS is typically a very crucial system, infinite loops must be prevented at all times. See how various SQL systems help you.
modern-sql.com/caniuse/with...
With recursive is the only SQL construct that is not guaranteed to terminate, eventually. As the DBMS is typically a very crucial system, infinite loops must be prevented at all times. See how various SQL systems help you.
Infinite Recursion Guards
Protection against infinite loops for WITH RECURSIVE.
modern-sql.com
February 2, 2026 at 2:37 PM
Infinite Recursion Guards
modern-sql.com/caniuse/with...
With recursive is the only SQL construct that is not guaranteed to terminate, eventually. As the DBMS is typically a very crucial system, infinite loops must be prevented at all times. See how various SQL systems help you.
modern-sql.com/caniuse/with...
With recursive is the only SQL construct that is not guaranteed to terminate, eventually. As the DBMS is typically a very crucial system, infinite loops must be prevented at all times. See how various SQL systems help you.
Time to re-watch The Terminator (1984)
February 1, 2026 at 1:36 PM
Time to re-watch The Terminator (1984)
If 26ai means 23.26.1 but not 23.26.0, then yes :)
January 28, 2026 at 2:51 PM
If 26ai means 23.26.1 but not 23.26.0, then yes :)
FILTER on modern-sql.com: modern-sql.com/feature/filter
The FILTER clause
The FILTER clause extends aggregate functions (SUM, AVG, COUNT, etc.) with an additional WHERE clause. Databases not supporting FILTER can use CASE within the aggregate function instead.
modern-sql.com
January 28, 2026 at 2:29 PM
FILTER on modern-sql.com: modern-sql.com/feature/filter
Oh, BTW, I’m also ecstatic about ASSERTION, but I’ll need some time to cover it on modern-sql.com.
January 28, 2026 at 2:28 PM
Oh, BTW, I’m also ecstatic about ASSERTION, but I’ll need some time to cover it on modern-sql.com.
FILTER was the first feature I covered on modern-sql.com, only supported by PostgreSQL at the time. In the meanwhile, half the system I cover support FILTER. Frankly speaking, I cannot understand why there are still systems not support such a simple, easy to understand and useful feature.
January 28, 2026 at 2:28 PM
FILTER was the first feature I covered on modern-sql.com, only supported by PostgreSQL at the time. In the meanwhile, half the system I cover support FILTER. Frankly speaking, I cannot understand why there are still systems not support such a simple, easy to understand and useful feature.
I’m a simple man.
While Oracle people are ecstatic about ASSERTION in the just released version 23.26.1 of the Oracle Database, I’m happy to see something as simple as FILTER :)
🧵
While Oracle people are ecstatic about ASSERTION in the just released version 23.26.1 of the Oracle Database, I’m happy to see something as simple as FILTER :)
🧵
January 28, 2026 at 2:28 PM
I’m a simple man.
While Oracle people are ecstatic about ASSERTION in the just released version 23.26.1 of the Oracle Database, I’m happy to see something as simple as FILTER :)
🧵
While Oracle people are ecstatic about ASSERTION in the just released version 23.26.1 of the Oracle Database, I’m happy to see something as simple as FILTER :)
🧵
Just in case you don’t know yet: use-the-index-luke.com
SQL Indexing and Tuning e-Book for developers: Use The Index, Luke covers Oracle, MySQL, PostgreSQL, SQL Server, ...
SQL indexing and tuning tutorial for developers. No unnecessary database details—just what developers need to know. Covers all major SQL databases.
use-the-index-luke.com
January 26, 2026 at 6:35 AM
Just in case you don’t know yet: use-the-index-luke.com
Permission granted ;) Go ahead.
I’d expect that the app should use prepared statements when it is designed to executes the same query often.
I’d expect that the app should use prepared statements when it is designed to executes the same query often.
January 24, 2026 at 5:33 PM
Permission granted ;) Go ahead.
I’d expect that the app should use prepared statements when it is designed to executes the same query often.
I’d expect that the app should use prepared statements when it is designed to executes the same query often.
Latencies are often
misunderstood. Also the IO latency in cloud environments, which are often many factors higher as on local discs (during development).
misunderstood. Also the IO latency in cloud environments, which are often many factors higher as on local discs (during development).
Many Small Queries Are Efficient in SQLite | Discussion
Many Small Queries Are Efficient In SQLite
www.sqlite.org
January 24, 2026 at 1:38 PM
Latencies are often
misunderstood. Also the IO latency in cloud environments, which are often many factors higher as on local discs (during development).
misunderstood. Also the IO latency in cloud environments, which are often many factors higher as on local discs (during development).
Probably coming in PostgreSQL 19, btw.
LEAD(x) IGNORE NULLS OVER(ORDER BY n)
Not very often, but when I need IGNORE NULLS, then I really miss it in PostgreSQL.
modern-sql.com/caniuse/T616
Not very often, but when I need IGNORE NULLS, then I really miss it in PostgreSQL.
modern-sql.com/caniuse/T616
T616, “Null treatment option for LEAD and LAG functions”
T616, “Null treatment option for LEAD and LAG functions” in SQL
modern-sql.com
January 23, 2026 at 8:09 AM
Probably coming in PostgreSQL 19, btw.
LEAD(x) IGNORE NULLS OVER(ORDER BY n)
Not very often, but when I need IGNORE NULLS, then I really miss it in PostgreSQL.
modern-sql.com/caniuse/T616
Not very often, but when I need IGNORE NULLS, then I really miss it in PostgreSQL.
modern-sql.com/caniuse/T616
T616, “Null treatment option for LEAD and LAG functions”
T616, “Null treatment option for LEAD and LAG functions” in SQL
modern-sql.com
January 22, 2026 at 12:47 PM
LEAD(x) IGNORE NULLS OVER(ORDER BY n)
Not very often, but when I need IGNORE NULLS, then I really miss it in PostgreSQL.
modern-sql.com/caniuse/T616
Not very often, but when I need IGNORE NULLS, then I really miss it in PostgreSQL.
modern-sql.com/caniuse/T616
From the license perspective a tarball would be fine.
But I think open source is more than that. For me it is a spectrum where MySQL is pretty close to the least openness.
But I think open source is more than that. For me it is a spectrum where MySQL is pretty close to the least openness.
January 22, 2026 at 8:54 AM
From the license perspective a tarball would be fine.
But I think open source is more than that. For me it is a spectrum where MySQL is pretty close to the least openness.
But I think open source is more than that. For me it is a spectrum where MySQL is pretty close to the least openness.
Reposted by Markus Winand
Recent posts made the point that MySQL is dying. One of the arguments was that there are no Git commits in the past months. This particular argument is totally misleading.
🧵
🧵
January 21, 2026 at 12:45 PM
Recent posts made the point that MySQL is dying. One of the arguments was that there are no Git commits in the past months. This particular argument is totally misleading.
🧵
🧵
The linked manual says
INSTALL COMPONENT 'file://classic_hashing'
but for me only
INSTALL COMPONENT 'file://component_classic_hashing'
works.
INSTALL COMPONENT 'file://classic_hashing'
but for me only
INSTALL COMPONENT 'file://component_classic_hashing'
works.
January 21, 2026 at 4:53 PM
The linked manual says
INSTALL COMPONENT 'file://classic_hashing'
but for me only
INSTALL COMPONENT 'file://component_classic_hashing'
works.
INSTALL COMPONENT 'file://classic_hashing'
but for me only
INSTALL COMPONENT 'file://component_classic_hashing'
works.
Charts on modern-sql.com updated for MySQL 9.6.0.
The functions MD5, SHA and SHA1 were "removed". That is (not very prominently) mentioned in the security section of the release notes.
You can get them back via
INSTALL COMPONENT 'file://component_classic_hashing'
dev.mysql.com/doc/refman/9...
The functions MD5, SHA and SHA1 were "removed". That is (not very prominently) mentioned in the security section of the release notes.
You can get them back via
INSTALL COMPONENT 'file://component_classic_hashing'
dev.mysql.com/doc/refman/9...
MySQL :: MySQL 9.6 Reference Manual :: 7.5.8 Legacy Hashing Component
dev.mysql.com
January 21, 2026 at 4:53 PM
Charts on modern-sql.com updated for MySQL 9.6.0.
The functions MD5, SHA and SHA1 were "removed". That is (not very prominently) mentioned in the security section of the release notes.
You can get them back via
INSTALL COMPONENT 'file://component_classic_hashing'
dev.mysql.com/doc/refman/9...
The functions MD5, SHA and SHA1 were "removed". That is (not very prominently) mentioned in the security section of the release notes.
You can get them back via
INSTALL COMPONENT 'file://component_classic_hashing'
dev.mysql.com/doc/refman/9...
Other arguments made in those recent posts may or may not be accurate. However, one may question to which extend Oracle’s Git push practice (among others) is in the spirit of open source.
The end.
The end.
January 21, 2026 at 12:45 PM
Other arguments made in those recent posts may or may not be accurate. However, one may question to which extend Oracle’s Git push practice (among others) is in the spirit of open source.
The end.
The end.