大约有 42,000 项符合查询结果（耗时：0.0496秒） [XML]
How to implement LIMIT with SQL Server?
I have this query with MySQL:
18 Answers
18
...
Null vs. False vs. 0 in PHP
...or a data value that doesn't exist in the database or is unknown. See dev.mysql.com/doc/refman/5.0/en/working-with-null.html or en.wikipedia.org/wiki/Null_%28SQL%29.
– Eli
Dec 5 '12 at 3:39
...
TCP 的那些事儿（下） - 更多技术 - 清泛网 - 专注C/C++及内核技术
...情况太糟糕，反应也很强烈。
sshthresh = cwnd /2
cwnd 重置为 1
进入慢启动过程
2）Fast Retransmit算法，也就是在收到3个duplicate ACK时就开启重传，而不用等到RTO超时。
TCP Tahoe的实现和RTO超时一样。
TCP Reno的...
How can I transform string to UTF-8 in C#?
...
If you want to save any string to mysql database do this:->
Your database field structure i phpmyadmin [ or any other control panel] should set to utf8-gerneral-ci
2) you should change your string [Ex. textbox1.text] to byte, therefor
2-1) define byte[]...
How to change a nullable column to not nullable in a Rails migration?
...
This worked for me. Using MySql locally. When pushed and ran app in Heroku (Postgres) it crapped on column that was not null when I was writing it a null - rightfully so. Only "change_column_null" would work could not use "change_column ... :null =>...
Define: What is a HashSet?
...ontains and Remove.) HashSet also provides standard set operations such as union, intersection, and symmetric difference. Take a look here
There are different implementations of Sets. Some make insertion and lookup operations super fast by hashing elements. However, that means that the order in whi...
Does a foreign key automatically create an index?
... I'm just about positive that PostgreSQL creates an index. I'm pretty sure MySQL does. Making the index makes a ton of sense, but IT'T NOT REQUIRED. After all, why reference something if every time the DB goes to look it up it has to do a tablescan?
– MBCook
Ma...
is it possible to select EXISTS directly as a bit?
... table (name nvarchar(16))
declare @b bit
insert @t select N'Simon Byorg' union select N'Roe Bott'
select @b = isnull((select top 1 1 from @t where name = N'Simon Byorg'),0)
select @b whenTrue
select @b = isnull((select top 1 1 from @t where name = N'Anne Droid'),0)
select @b whenFalse
...
SQL - using alias in Group By
...OUP BY is executed before the SELECT clause.
There are exceptions though: MySQL and Postgres seem to have additional smartness that allows it.
share
|
improve this answer
|
...
What's the longest possible worldwide phone number I should consider in SQL varchar(length) for phon
...
I know that should be the case, but it's not always. In MySQL (for example) the full length is used for sorting. It's best to apply at least some minimal effort.
– Morgan Tocker
Jul 20 '10 at 18:23
...