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SQL Server - When to use Clustered vs non-Clustered Index?
...k a good clustered index.
It's the most replicated data structure in your SQL Server database. The clustering key will be part of each and every non-clustered index on your table, too.
You should use extreme care when picking a clustering key - it should be:
narrow (4 bytes ideal)
unique (it's t...
How to randomly select rows in SQL?
I am using MSSQL Server 2005. In my db, I have a table "customerNames" which has two columns "Id" and "Name" and approx. 1,000 results.
...
How to generate the “create table” sql statement for an existing table in postgreSQL
I have created a table in postgreSQL. I want to look at the SQL statement used to create the table but cannot figure it out.
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How to get cumulative sum
...in @t t2 on t1.id >= t2.id
group by t1.id, t1.SomeNumt
order by t1.id
SQL Fiddle example
Output
| ID | SOMENUMT | SUM |
-----------------------
| 1 | 10 | 10 |
| 2 | 12 | 22 |
| 3 | 3 | 25 |
| 4 | 15 | 40 |
| 5 | 23 | 63 |
Edit: this is a generalized...
SEH stack 结构探索（1）--- 从 SEH 链的最底层（线程第1个SEH结构）说起 -...
... _EXCEPTION_REGISTRATION_RECORD 结构，我们最好准备纸笔记录下它的 stack 变化情况
1. ntdll32!_SEH_prolog4() 构造的 stack 结构
刚进入 ntdll32!_SEH_prolog4() 时的 stack 是下面的图
上面的两个返回地址一个是返回到 ntdll32!_RtlUserThreadStart() 一...
Naming of ID columns in database tables
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ID is a SQL Antipattern.
See http://www.amazon.com/s/ref=nb_sb_ss_i_1_5?url=search-alias%3Dstripbooks&field-keywords=sql+antipatterns&sprefix=sql+a
If you have many tables with ID as the id you are making reporting that muc...
How to get sp_executesql result into a variable?
I have a piece of dynamic SQL I need to execute, I then need to store the result into a variable.
10 Answers
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Error in SQL script: Only one statement is allowed per batch
I have 4 sql scripts that I want to run in a DACPAC in PostDeployment, but when I try to build the VS project for 3 of them I get this error:
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Strange SQLAlchemy error message: TypeError: 'dict' object does not support indexing
I am using hand crafted SQL to fetch data from a PG database, using SqlAlchemy. I am trying a query which contains the SQL like operator '%' and that seems to throw SqlAlcjhemy through a loop:
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Which method performs better: .Any() vs .Count() > 0?
...but if you have part of code that's slow and it uses EF, test with direct TSQL and compare performance rather than relying on assumptions (that .Any() is ALWAYS faster than .Count() > 0).
While I agree with most up-voted answer and comments - especially on the point Any signals developer inten...