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Convert a date format in PHP
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What if I get this date 0000-00-00 from mySQL? it returns a wrong date like 31/12/1969 ...
– Enrique
Apr 29 '10 at 22:20
3
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ALTER TABLE to add a composite primary key
...r table you will get an error when trying to drop it. In some versions of mysql the error message there was malformed (as of 5.5.17, this error message is still
alter table parent drop column id;
ERROR 1025 (HY000): Error on rename of
'./test/#sql-a04_b' to './test/parent' (errno: 150).
If you ...
What data type to use for hashed password field and what length?
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You can actually use CHAR(length of hash) to define your datatype for MySQL because each hashing algorithm will always evaluate out to the same number of characters. For example, SHA1 always returns a 40-character hexadecimal number.
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Remove all spaces from a string in SQL Server
...ct
'"' + c + '"' [IN], '"' + replace(c, ' ', '') + '"' [OUT]
from #t
union all select
'"' + v + '"', '"' + replace(v, ' ', '') + '"'
from #t
Result
IN OUT
===================
"a a " "aa"
"a a " "aa"
" a a " "aa"
" a a " "aa"
"a a" "aa"...
PHP编译configure时常见错误 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...e gmp.h
centos: yum install gmp-devel
14、Configure: error: Cannot find MySQL header files under /usr. Note that the MySQL client library is not bundled anymore!
yum install mysql-devel (For Redhat & Fedora)
# apt-get install libmysql++-dev (For Ubuntu)
15、Configure: error: Please reinstall ...
How to get last inserted row ID from WordPress database?
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Putting the call to mysql_insert_id() inside a transaction, should do it:
mysql_query('BEGIN');
// Whatever code that does the insert here.
$id = mysql_insert_id();
mysql_query('COMMIT');
// Stuff with $id.
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Why historically do people use 255 not 256 for database field magnitudes?
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255 was the varchar limit in mySQL4 and earlier.
Also 255 chars + Null terminator = 256
Or 1 byte length descriptor gives a possible range 0-255 chars
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Checking if a field contains a string
.../reference/sql-comparison/
http://php.net/manual/en/mongo.sqltomongo.php
MySQL
SELECT * FROM users WHERE username LIKE "%Son%"
MongoDB
db.users.find({username:/Son/})
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Windows下 C++网络延时检测 - C/C++ - 清泛网 - 专注C/C++及内核技术
...低延时、负载较低的服务器节点。例如：那么这个功能是如何实现的呢？...一般需要连接服务器后端的软件都有服务器节点网络延迟的检测，帮助选择低延时、负载较低的服务器节点。例如：
那么这个功能是如何实现的呢？...
中关村服务辐射百万创业者 - 资讯 - 清泛网 - 专注C/C++及内核技术
...间、人才、资本……成为拦在创业道路上的种种难题。
如何才能在日益变化的环境下更好地帮到创业者，成为摆在创业服务业面前的最大问题。6月25日，清控科创携手清华控股、北极光创投、完美时空、银杏天使、创业邦、盛...