引言 I know, we can not rename a column using modify column syntax,but can change column syntax. My question is: what is the main usage of modify syntax? For example, alter table tablename change col1 col1 int(10) not null instead of alter table tablen
ALTER COLUMN.MODIFY COLUMN 和 CHANGE COLUMN 语句修改列: ALTER COLUMN:改变.删除列的默认值(备注:列的默认值存储在 .frm 文件中). 这个语句会直接修改 .frm 文件而不涉及表数据,所以操作很快. -- 改变列的默认值 ALTER TABLE test ALTER COLUMN age SET DEFAULT 17; -- 删除列的默认值 ALTER TABLE test ALTER COLUMN age DROP DEFAULT;
Utilities type // is this a function? typeof someValue === 'function'; // is this an object? someValue != null && Object.prototype.toString.call(someValue) === "[object Object]"; // works in modern browsers Array.isArray(someValue); // w
Avoid duplicate symbol in static library and its customer 发布static library给使用者使用.在实际的工程实践中,iOS静态库一般会在对外/对内提供SDK时出现. 静态库(SDK)本身可能依赖一些第三方的库,当使用该SDK的App也依赖了同样的第三方库,那么问题就来啦. Figure: SDK 和 SDK Customer 依赖相同的3rd library 1. static library如何避免和使用者的代码有重复符号 Re
Cat stands for concatenate. Case 1. When the text files have more blank lines, we want to remove them. We can use regex \s+ '\n'. cat file.txt | tr \s '\n' cat -T file.txt # show tabs as ^. cat -n file.txt # show line numbers . Specifies current dire
Given an integer array in the construct method, implement two methods query(start, end) and modify(index, value): For query(start, end), return the sum from index start to index end in the given array. For modify(index, value), modify the number in t
How To Use Git Source Control with Xcode in iOS 6 If you're new here, you may want to subscribe to my RSS feed or follow me on Twitter. Thanks for visiting! How to use Git source control with Xcode This tutorial is by Malek Trabelsi, a passionate iOS
/* CR#1796870 modify by v-yangwu, add a js file to control the page controls. */ $(document).ready(function () { $('#radioExtranet').on('click', function () { showProjectInformation() }); $('#radioCorp').on('click', function () { hideProjectInformati
commands : show sys connect sys as sysdba or connect system as sysdba logout or disc clear screen or cle screen (utlsample.sql —> unlock scott tables.sql —> all tables data.sql —> add data into tables) connect scott/tiger start C:\utlsample.sq
http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.faqs/ka10535.html C166: START167 AND BOOT167 QUESTION I do not quite understand the files START167.A66 and BOOT167.A66. Is BOOT.A66 used for the monitor and START167.A66 used for the final a
