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Create unique constraint with null columns
...otal on top).
Aside: I advise not to use mixed case identifiers in PostgreSQL.
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Computed / calculated / virtual / derived columns in PostgreSQL
Does PostgreSQL support computed / calculated columns, like MS SQL Server? I can't find anything in the docs, but as this feature is included in many other DBMSs I thought I might be missing something.
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sqlite3.ProgrammingError: Incorrect number of bindings supplied. The current statement uses 1, and t
... is also not recommended for security concerns - docs.python.org/3/library/sqlite3.html
– wesinat0r
Jul 6 at 14:57
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C# Lambda expressions: Why should I use them?
...erted to expression trees which allows for a lot of the magic like LINQ to SQL.
The following is an example of a LINQ to Objects expression using anonymous delegates then lambda expressions to show how much easier on the eye they are:
// anonymous delegate
var evens = Enumerable
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Difference between CLOB and BLOB from DB2 and Oracle Perspective?
... DB2: http://pic.dhe.ibm.com/infocenter/db2luw/v10r5/topic/com.ibm.db2.luw.sql.ref.doc/doc/r0008473.html
SQL and XML limits: http://pic.dhe.ibm.com/infocenter/db2luw/v10r5/topic/com.ibm.db2.luw.sql.ref.doc/doc/r0001029.html
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创业公司如何实施敏捷开发 - 资讯 - 清泛网 - 专注C/C++及内核技术
...业公司敏捷开发任务墙
每日站立会议大家认领任务。包括业务任务、开发设计、开发编码、前端设计开发、测试等都是一个个任务，统一管理起来。强调的是一个团体，如果有同事请假，其他同事可以顶上完成任务。站立会...
PostgreSQL delete with inner join
i am getting the following error PostgreSQL 8.2.11
5 Answers
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How accurately should I store latitude and longitude?
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If you're using SQL Server... It's worth noting that a precision of 1-9 uses 5 bytes. So you may was well use a decimal(9,6) instead of decimal(7,4) and take advantage of the higher accuracy since they both occupy the same amount of space.
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关于php的socket初探 - PHP - 清泛IT论坛，有思想、有深度
...些多路复用的模式中，异步阻塞/非阻塞模式的扩展性和性能最好。
引入阻塞/非阻塞,、同步/异步比喻很形象的一段话：
有A，B，C，D四个人在钓鱼：
A用的是最老式的鱼竿，所以呢，得一直守着，等到鱼上钩了再拉杆；
B的...
ros 基本调试 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...条请牢记：
■计划好哪个连接是DTE，哪个是DCE，它们各包括什么类型，牢记你在这两台电脑上各使用了哪个端口（1还是2）。
■制作正确的null modem线。制作null modem线有多种方法，采用不同的方法做出来的线都是不一样的。
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