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Add a column to a table, if it does not already exist
I want to write a query for MS SQL Server that adds a column into a table. But I don't want any error display, when I run/execute the following query.
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T-SQL - function with default parameters
... answered Dec 2 '11 at 15:11
SQLMenaceSQLMenace
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Simplest way to do a recursive self-join?
What is the simplest way of doing a recursive self-join in SQL Server? I have a table like this:
5 Answers
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创业公司倒闭大潮 教你正确烧钱速度？ - 资讯 - 清泛网 - 专注C/C++及内核技术
...你要多快再融资，以及正面对的风险；对潜在投资人，还包括你需要多少钱。如果你很赶，那么你对投资人的杠杆作用也就越低。
另外我经常看到一些公司：月净现金消耗量只有10万，却希望融600-800万。我第一个问题就会问：
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Find nearest latitude/longitude with an SQL query
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Google's solution:
Creating the Table
When you create the MySQL table, you want to pay particular attention to the lat and lng attributes. With the current zoom capabilities of Google Maps, you should only need 6 digits of precision after the decimal. To keep the storage space require...
Does Foreign Key improve query performance?
...Keys are a referential integrity tool, not a performance tool. At least in SQL Server, the creation of an FK does not create an associated index, and you should create indexes on all FK fields to improve look up times.
shar...
Dokan虚拟磁盘开发实战 - 操作系统(内核) - 清泛网 - 专注C/C++及内核技术
...le里搜索，或到Dokan的官方网站去下载(Dokan官网)，源码是C语言的，应用例子有Ruby、.Net及C的。如果想要Delphi的例子代码，只能自己去找了。
刚开始时由于不清楚如何用Dokan来实现一个文件系统，所以需要做一些试验，结果一不...
LINQ to SQL - Left Outer Join with multiple join conditions
I have the following SQL, which I am trying to translate to LINQ:
6 Answers
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Better techniques for trimming leading zeros in SQL Server?
...rflow.com/questions/662383/better-techniques-for-trimming-leading-zeros-in-sql-server
DECLARE @retVal VarChar(128),
@pattern varChar(10)
SELECT @pattern = '%[^'+@stripChar+']%'
SELECT @retVal = CASE WHEN SUBSTRING(@string, PATINDEX(@pattern, @string+'.'), LEN(@string)) = '' T...
Generating a UUID in Postgres for Insert statement?
...default. You must load it into your database to use it.
For modern PostgreSQL versions (9.1 and newer) that's easy:
CREATE EXTENSION IF NOT EXISTS "uuid-ossp";
but for 9.0 and below you must instead run the SQL script to load the extension. See the documentation for contrib modules in 8.4.
For...