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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...
PHP学习必看的一些书 - PHP - 清泛IT论坛，有思想、有深度
...还不错，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》 –关于很多架构和...
MySQL date format DD/MM/YYYY select query?
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You can use STR_TO_DATE() to convert your strings to MySQL date values and ORDER BY the result:
ORDER BY STR_TO_DATE(datestring, '%d/%m/%Y')
However, you would be wise to convert the column to the DATE data type instead of using strings.
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Best data type for storing currency values in a MySQL database
What is the best SQL data type for currency values? I'm using MySQL but would prefer a database independent type.
9 Answer...
How to get the mysql table columns data type?
I want to get the column data type of a mysql table.
11 Answers
11
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Include all existing fields and add new fields to document
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You can use $$ROOT to references the root document. Keep all fields of this document in a field and try to get it after that (depending on your client system: Java, C++, ...)
[
{
$project: {
custom_field: "$obj.ob...
How to pass arguments to a Button command in Tkinter?
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Example GUI:
Let's say I have the GUI:
import tkinter as tk
root = tk.Tk()
btn = tk.Button(root, text="Press")
btn.pack()
root.mainloop()
What Happens When a Button Is Pressed
See that when btn is pressed it calls its own function which is very similar to button_press_handle in t...