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C Macro definition to determine big endian or little endian machine?
... = 0x02030001ul /* Honeywell 316 (aka ENDIAN_BIG_WORD) */
};
static const union { unsigned char bytes[4]; uint32_t value; } o32_host_order =
{ { 0, 1, 2, 3 } };
#define O32_HOST_ORDER (o32_host_order.value)
#endif
You would check for little endian systems via
O32_HOST_ORDER == O32_LITTLE_E...
#1071 - Specified key was too long; max key length is 767 bytes
...
767 bytes is the stated prefix limitation for InnoDB tables in MySQL version 5.6 (and prior versions). It's 1,000 bytes long for MyISAM tables. In MySQL version 5.7 and upwards this limit has been increased to 3072 bytes.
You also have to be aware that if you set an index on a big char ...
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
15
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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 They are no longer maintained and are officially deprecated.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...
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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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...
Is there a Max function in SQL Server that takes two values like Math.Max in .NET?
...he "best answer" because:
It doesn't require complicating your code with UNION's, PIVOT's,
UNPIVOT's, UDF's, and crazy-long CASE statments.
It isn't plagued with the problem of handling nulls, it handles them just fine.
It's easy to swap out the "MAX" with "MIN", "AVG", or "SUM". You can use any ...
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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