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PHP date() format when inserting into datetime in MySQL
...pass to the date() function in PHP if I want to insert the result into a MySQL datetime type column?
13 Answers
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How big can a MySQL database get before performance starts to degrade
At what point does a MySQL database start to lose performance?
15 Answers
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java.sql.SQLException: Incorrect string value: '\xF0\x9F\x91\xBD\xF0\x9F…'
...rs and one will see squares if you are not using fonts that support them.
MySQL's utf8 only supports basic multilingual plane, and you need to use utf8mb4 instead:
For a supplementary character, utf8 cannot store the character at all,
while utf8mb4 requires four bytes to store it. Since utf8 ...
Reference - What does this error mean in PHP?
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Warning: mysql_fetch_array() expects parameter 1 to be resource, boolean given
First and foremost:
Please, don't use mysql_* functions in new code. They are no longer maintained and are officially deprecated. See the red box? Lea...
MySQL order by before group by
...pand on my comments about using a subquery to accurate return this data.
MySQL does not force you to GROUP BY every column that you include in the SELECT list. As a result, if you only GROUP BY one column but return 10 columns in total, there is no guarantee that the other column values which bel...
What's faster, SELECT DISTINCT or GROUP BY in MySQL?
...doesn't have to sort the output, and GROUP BY by default does. However, in MySQL even a DISTINCT+ORDER BY might still be faster than a GROUP BY due to the extra hints for the optimizer as explained by SquareCog.
– rustyx
Jan 25 '15 at 15:03
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how to customize `show processlist` in mysql?
...any way you like.
The INFORMATION_SCHEMA.PROCESSLIST table was added in MySQL 5.1.7. You can find out which version you're using with:
SELECT VERSION()
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Rank function in MySQL
...NSI standard SQL query for my requirement. Please help me to convert it to MySQL .
11 Answers
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内存管理内幕：动态分配的选择、折衷和实现 - C/C++ - 清泛网 - 专注C/C++及内核技术
...点是 C 语言，但同样也适用于其他语言。文中将为您提供如何管理内存的细节，然后将进一步展示如何手工管理内存，如何使用引用计数或者内存池来半手工地管理内存， 以及如何使用垃圾收集自动管理内存。为什么必须管理...
MySQL: Set user variable from result of query
Is it possible to set an user variable based on the result of a query in MySQL?
4 Answers
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