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How does MySQL process ORDER BY and LIMIT in a query?
... @Green, you're mistaken. Read this for the explanation: dev.mysql.com/doc/refman/5.7/en/limit-optimization.html When the ORDER BY column is indexed, it may return records in a different order than without the LIMIT, when there are more than 1 records with the same value in that column...
What are the best PHP input sanitizing functions?
...to the server. If you haven't worked with PDO before here's a pretty good MySQL-oriented tutorial.
Some SQL databases have their own specialty extensions in PHP, including SQL Server, PostgreSQL and SQLite 3. Each of those extensions has prepared statement support that operates in the same prepare...
MySQL's now() +1 day
I'm using now() in MySQL query.
4 Answers
4
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How can you determine how much disk space a particular MySQL table is taking up?
Is there a quick way to determine how much disk space a particular MySQL table is taking up? The table may be MyISAM or Innodb.
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1114 (HY000): The table is full
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@Nadh In Ubuntu 16.04 it's part of /etc/mysql/ and is partly splitted into additional files in /etc/mysql/conf.d
– Martin C.
Jun 17 '17 at 22:01
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MySQL INSERT INTO table VALUES.. vs INSERT INTO table SET
...ll, both syntaxes are equivalent. The first is SQL standard, the second is MySQL's extension.
So they should be exactly equivalent performance wise.
http://dev.mysql.com/doc/refman/5.6/en/insert.html says:
INSERT inserts new rows into an existing table. The INSERT ... VALUES and INSERT ... SET...
How to debug PDO database queries?
...ments to Rails, but that the benefit is much heavier in PostgreSQL than in MySQL. He said that this is because MySQL doesn't actually create the query plan until you execute the prepared query.
– Nathan Long
Jul 20 '11 at 13:46
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使用虚拟现实和App Inventor进行实验 · App Inventor 2 中文网
...Google 商店以查找各种 Cardboard 查看器，或在网上搜索有关如何制作自己的 Cardboard 查看器的提示。您还可以使用 Cardboard 以外的查看器。
Expeditions
Expeditions 演示显示沉浸式 360 度全景图。Google 于 2014 年在 Google I/O 2014 的主题演讲...
How do I check to see if a value is an integer in MySQL?
I see that within MySQL there are Cast() and Convert() functions to create integers from values, but is there any way to check to see if a value is an integer? Something like is_int() in PHP is what I am looking for.
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Importance of varchar length in MySQL table
I have a MySQL table where rows are inserted dynamically. Because I can not be certain of the length of strings and do not want them cut off, I make them varchar(200) which is generally much bigger than I need. Is there a big performance hit in giving a varchar field much more length than necessar...