Should I use the datetime or timestamp data type in MySQL?

Would you recommend using a datetime or a timestamp field, and why (using MySQL)? I'm working with PHP on the server side. Timestamps in MySQL are generally used to track changes to records, and are often updated every time the record is changed. If you want to store a specific value you should use a datetime field. If you meant that you want to decide between using a UNIX timestamp or


你会推荐使用日期时间或时间戳字段,以及为什么(使用MySQL)? 我正在服务器端使用PHP。 MySQL中的时间戳通常用于跟踪对记录的更改,并且每次记录更改时都会更新。 如果你想存储一个特定的值,你应该使用日期时间字段。 如果您的意思是您想要决定使用UNIX时间戳还是本地MySQL日期时间字段,请使用本机格式。 您可以用这种方式在MySQL中进行计算("SELECT DATE_ADD(my_datetime, INTERVAL 1 DAY)")并且在查询记

How can I prevent SQL injection in PHP?

If user input is inserted without modification into an SQL query, then the application becomes vulnerable to SQL injection, like in the following example: $unsafe_variable = $_POST['user_input']; mysql_query("INSERT INTO `table` (`column`) VALUES ('$unsafe_variable')"); That's because the user can input something like value'); DROP TABLE table;-- value'); DROP TABLE table;-- , an


如果用户输入未经修改而插入到SQL查询中,则该应用程序容易受到SQL注入的影响,如下例所示: $unsafe_variable = $_POST['user_input']; mysql_query("INSERT INTO `table` (`column`) VALUES ('$unsafe_variable')"); 这是因为用户可以输入类似value'); DROP TABLE table;--东西value'); DROP TABLE table;-- value'); DROP TABLE table;-- ,查询变为: INSERT INTO `table` (`column`) VALUES('value'); DRO

Convert HTML + CSS to PDF with PHP?

I have an HTML (not XHTML) document that renders fine in Firefox 3 and IE 7. It uses fairly basic CSS to style it and renders fine in HTML. I'm now after a way of converting it to PDF. I have tried: DOMPDF: it had huge problems with tables. I factored out my large nested tables and it helped (before it was just consuming up to 128M of memory then dying--thats my limit on memory in php.i


我有一个在Firefox 3和IE 7中呈现良好的HTML(不是XHTML)文档。它使用相当基本的CSS来设计它,并且在HTML中渲染得很好。 我现在正在将它转换为PDF。 我努力了: DOMPDF:它有很多表格问题。 我分解了我的大型嵌套表,并且它有所帮助(在它耗尽高达128M的内存然后死亡之前 - 这是我在php.ini中对内存的限制),但是它使得表格变得非常混乱,似乎并没有得到图片。 这些表只是基本的东西,有些边框样式可以在不同的点添加一

How do I check if a string contains a specific word?

Consider: $a = 'How are you?'; if ($a contains 'are') echo 'true'; Suppose I have the code above, what is the correct way to write the statement if ($a contains 'are') ? You can use the strpos() function which is used to find the occurrence of one string inside another one: $a = 'How are you?'; if (strpos($a, 'are') !== false) { echo 'true'; } Note that the use of !== fals


考虑: $a = 'How are you?'; if ($a contains 'are') echo 'true'; 假设我有上面的代码,写下语句if ($a contains 'are')的正确方法if ($a contains 'are')什么? 你可以使用strpos()函数来查找一个字符串在另一个字符串中的出现: $a = 'How are you?'; if (strpos($a, 'are') !== false) { echo 'true'; } 请注意,使用!== false是故意的; strpos()返回干草堆字符串中针串开始的偏移量,或

Reference — What does this symbol mean in PHP?

What is this? This is a collection of questions that come up every now and then about syntax in PHP. This is also a Community Wiki, so everyone is invited to participate in maintaining this list. Why is this? It used to be hard to find questions about operators and other syntax tokens.¹ The main idea is to have links to existing questions on Stack Overflow, so it's easier for us to r

参考 - 这个符号在PHP中的含义是什么?

这是什么? 这是一个关于PHP中语法问题的集合。 这也是一个社区Wiki,所以每个人都被邀请参与维护这个列表。 为什么是这样? 过去很难找到关于运算符和其他语法令牌的问题 主要想法是链接到堆栈溢出的现有问题,所以我们更容易引用它们,而不是复制PHP手册中的内容。 ¹注意:自2013年1月以来,Stack Overflow确实支持特殊字符。 只需通过引号括住搜索词,例如[php] "==" vs "===" 我应该在这