大约有 40,000 项符合查询结果（耗时：0.0238秒） [XML]
What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
...cally, a lot of dbms have been quite poor when it comes to handling joins (MySQL being a particularly noteworthy example). So n+1 has, often, been notably faster than a join. And then there are ways to improve on n+1 but still without needing a join, which is what the original problem relates to.
H...
PostgreSQL Autoincrement
I'm switching from MySQL to PostgreSQL and was wondering how I can do autoincrement values. I saw in the PostgreSQL docs a datatype "serial", but I get syntax errors when using it (in v8.0).
...
How does this giant regex work?
...pecially FTP, although should be using sftp or ftps.
If you control your MySQL server make sure your web application's MySQL user account is not root, and make sure you remove MySQL FILE privileges from the account. You should also go a step further and do a chmod 500 -R /path/to/web/root and d...
Increment value in mysql update query
...
You could also just do this:
mysql_query("
UPDATE member_profile
SET points = points + 1
WHERE user_id = '".$userid."'
");
share
|
improve...
MySQL search and replace some text in a field
What MySQL query will do a text search and replace in one particular field in a table?
7 Answers
...
When to use single quotes, double quotes, and backticks in MySQL
...le and column identifiers, but are only necessary when the identifier is a MySQL reserved keyword, or when the identifier contains whitespace characters or characters beyond a limited set (see below) It is often recommended to avoid using reserved keywords as column or table identifiers when possibl...
How do I insert NULL values using PDO?
...
I had trouble with PDO::PARAM_NULL on MySql 5.1.53, but PDO::PARAM_INT with a null value worked great.
– Will Shaver
Dec 5 '11 at 19:33
2
...
phpmyadmin logs out after 1440 secs
In my local development Ubuntu box I use MySQL and phpmyadmin to work with the database.
24 Answers
...
How to execute a raw update sql with dynamic binding in rails
...d try accessing the underlying connection and using it's methods, e.g. for MySQL:
st = ActiveRecord::Base.connection.raw_connection.prepare("update table set f1=? where f2=? and f3=?")
st.execute(f1, f2, f3)
st.close
I'm not sure if there are other ramifications to doing this (connections left op...
Preserve Line Breaks From TextArea When Writing To MySQL
...s two method steps for preserve same text which is in textarea to store in mysql
and at a getting time i can also simply displaying plain text.....
step 1:
$status=$_POST['status'];<br/>
$textToStore = nl2br(htmlentities($status, ENT_QUOTES, 'UTF-8'));
In query enter $textToStore....
step 2:
...