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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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WITH CHECK ADD CONSTRAINT followed by CHECK CONSTRAINT vs. ADD CONSTRAINT
I'm looking at the AdventureWorks sample database for SQL Server 2008, and I see in their creation scripts that they tend to use the following:
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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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INT 10H 中断介绍 - C/C++ - 清泛网 - 专注C/C++及内核技术
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INT 10H 是由 BIOS 对屏幕及显示器所提供的服务程序。使用 INT 10H 中断服务程序时，先指定 AH 寄存器为下表编号其中之一，该编号表示欲调用的功用，而其他寄存器的详细说明，参考表后文字，当一切设定好之后再调用 INT 10H...
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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SQLite select where empty?
In SQLite, how can I select records where some_column is empty?
Empty counts as both NULL and "".
4 Answers
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