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Oracle Differences between NVL and Coalesce
...guments to be of same datatype.
COALESCE gives issues in queries which use UNION clauses. Example
below
COALESCE is ANSI standard where as NVL is Oracle specific.
Examples for the third case. Other cases are simple.
select nvl('abc',10) from dual; would work as NVL will do an implicit conversion ...
Add list to set?
...
With respect to sets, the | operator implements the set union operation. Both the |= operator and set.update() method apply that operation in-place and are effectively synonymous. So, set_a |= set_b could be considered syntactic sugar for both set_a.update(set_b) and set_a = set_a...
Creating a config file in PHP
...ction to escape data for embedding into PHP code as exists for HTML, URLs, MySQL statements, shell commands....
Serialized data
This is relatively efficient for small amounts of configuration (up to around 200 items) and allows for use of any PHP data structure. It requires very little code to crea...
Insert multiple rows WITHOUT repeating the “INSERT INTO …” part of the statement?
...
INSERT INTO dbo.MyTable (ID, Name)
SELECT 123, 'Timmy'
UNION ALL
SELECT 124, 'Jonny'
UNION ALL
SELECT 125, 'Sally'
For SQL Server 2008, can do it in one VALUES clause exactly as per the statement in your question (you just need to add a comma to separate each values statement)....
实战Nginx与PHP(FastCGI)的安装、配置与优化 - 更多技术 - 清泛网 - 专注...
...进行了详细介绍,这里不再进行讲述。下面重点介绍Nginx如何通过php-fpm的FastCGI进程对PHP进行解析处理。
由于Nginx本身不会对PHP进行解析,因此要实现Nginx对PHP的支持,其实是将对PHP页面的请求交给fastCGI进程监听的IP地址及端口...
Should I add .vcxproj.filter files to source control?
...st found that if you use Git you can mark .filter files to be treated as a union for merging to make it simpler. Just add the line:
*.vcxproj.filters merge=union
to your .gitattributes file.
See Using .gitattributes to avoid merge conflicts for more details.
...
When to use Common Table Expression (CTE)
... ,null AS Answer
,1 AS Is_Question
FROM [Questions]
UNION ALL
SELECT Q.[Quiz_ID]
,[Question_ID]
,A.[ID] AS Answer_Id
,Q.Question_Text
,[Answer]
,0 AS Is_Question
FROM [Answers] A INNER JOIN [Questions] Q ON Q.Quiz_ID = A.Quiz...
How to rollback a specific migration?
... probably true only for databases which doesn't support Transactional DDL. MySQL doesn't support Transactional DDL: dev.mysql.com/doc/refman/5.0/en/cannot-roll-back.html PostreSQL does: wiki.postgresql.org/wiki/… So if your migration on MySQL database is broken then you have manually to delete pa...
Adding a public key to ~/.ssh/authorized_keys does not log me in automatically
...ider the excellent http://www.fail2ban.org
8. Extra
SSH tunnel to access a MySQL (bind = 127.0.0.1) server
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What is the difference between 'protected' and 'protected internal'?
...
The "protected internal" access modifier is a union of both the "protected" and "internal" modifiers.
From MSDN, Access Modifiers (C# Programming Guide):
protected:
The type or member can be accessed only by code in the same class or
struct, or in a class that is...