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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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How add context menu item to Windows Explorer for folders [closed]
...ws Explorer or on background of a directory in right panel:
HKEY_CLASSES_ROOT\Directory\Background\shell if you are administrator
HKEY_CURRENT_USER\Software\Classes\directory\Background\shell if you are a normal user
Context menu for right click on folders in right panel of Windows Explorer:
H...
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...
Real escape string and PDO [duplicate]
I'm using PDO after migrating away from the mysql library. What do I use in place of the old real_escape_string function?
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Ioc/DI - Why do I have to reference all layers/assemblies in application's entry point?
...osely coupled application, by moving all the references to the Composition Root, the dependency graph is severely flattened:
As illustrated by the green color, it's now possible to reuse Library C without dragging along any unwanted dependencies.
However, all that said, with many DI Containers, ...
When NOT to use Cassandra?
...ase of RDBMS, making a choice is quite easy because all the databases like MySQL, Oracle, MS SQL, PostgreSQL in this category offer almost the same kind of solutions oriented toward ACID properties. When it comes to NoSQL, the decision becomes difficult because every NoSQL database offers different ...
How to delete a column from a table in MySQL
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Here's a working example.
Note that the COLUMN keyword is optional, as MySQL will accept just DROP IsDeleted. Also, to drop multiple columns, you have to separate them by commas and include the DROP for each one.
ALTER TABLE tbl_Country
DROP COLUMN IsDeleted,
DROP COLUMN CountryName;
This...
Mysql substr和Oracle substr区别 - 数据库(内核) - 清泛网 - 专注C/C++及内核技术
Mysql substr和Oracle substr区别Oracle substr(字符串，开始索引、从0起，长度)Mysql substr或substring(字符串，开始索引、从1起，长度)Oracle substr(字符串，开始索引、从0起，长度)
Mysql substr或substring(字符串，开始索引、从1起，长度)Mysql Orac...
mysql实现split分割字符串（length, SUBSTRING_INDEX, substring） - 数据...
mysql实现split分割字符串（length, SUBSTRING_INDEX, substring）由于MySql没有直接的split函数，只提供了length, SUBSTRING_INDEX, substring三个函数，这里介绍如何用这三个函数实现split功能。# SUBS...由于MySql没有直接的split函数，只提供了length, SUB...
PHP学习必看的一些书 - IT书籍推荐 - 清泛网 - 专注C/C++及内核技术
...不错，对于框架介绍和开发来说
数据库相关（主要是Mysql）
《MySQL必知必会》 –极好的MySQL语法参考书
《深入浅出MySQL——数据库开发、优化与管理维护》 –很多实用的MySQL技巧
《MySQL性能调优与架构设计》 –关...