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How do I check to see if a value is an integer in MySQL?
I see that within MySQL there are Cast() and Convert() functions to create integers from values, but is there any way to check to see if a value is an integer? Something like is_int() in PHP is what I am looking for.
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Importance of varchar length in MySQL table
I have a MySQL table where rows are inserted dynamically. Because I can not be certain of the length of strings and do not want them cut off, I make them varchar(200) which is generally much bigger than I need. Is there a big performance hit in giving a varchar field much more length than necessar...
Types in MySQL: BigInt(20) vs Int(20)
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See http://dev.mysql.com/doc/refman/8.0/en/numeric-types.html
INT is a four-byte signed integer.
BIGINT is an eight-byte signed integer.
They each accept no more and no fewer values than can be stored in their respective number of by...
App Inventor 2 接入百度网盘API · App Inventor 2 中文网
...框】
接入文档
使用Web浏览框，里面要输入网盘用户名密码，成功后返回的url中拿出access_token
这里使用简单模式，回调网页，在回调后的URL中拿出access_token，后面操作都需要它：
http://openapi.baidu.com/oauth/2.0/authorize?display=mobil...
How to subtract 30 days from the current datetime in mysql?
How do I subtract 30 days from the current datetime in mysql?
8 Answers
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Is it a good idea to index datetime field in mysql?
...etime clause to select data. Is it a good idea to index datetime fields in mysql database?
2 Answers
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Dropping Unique constraint from MySQL table
How can I drop the "Unique Key Constraint" on a column of a MySQL table using phpMyAdmin?
10 Answers
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使用虚拟现实和App Inventor进行实验 · App Inventor 2 中文网
...Google 商店以查找各种 Cardboard 查看器，或在网上搜索有关如何制作自己的 Cardboard 查看器的提示。您还可以使用 Cardboard 以外的查看器。
Expeditions
Expeditions 演示显示沉浸式 360 度全景图。Google 于 2014 年在 Google I/O 2014 的主题演讲...
What does `unsigned` in MySQL mean and when to use it?
What does "unsigned" mean in MySQL and when should I use it?
1 Answer
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Maximum length of a table name in MySQL
What is the maximum length of a table name in MySQL?
4 Answers
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