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SQL Joins Vs SQL Subqueries (Performance)?
... and an explicit JOIN. In my experience IN is a very slow operator, since SQL normally evaluates it as a series of WHERE clauses separated by "OR" (WHERE x=Y OR x=Z OR...).
As with ALL THINGS SQL though, your mileage may vary. The speed will depend a lot on indexes (do you have indexes on both I...
SQL - Query to get server's IP address
Is there a query in SQL Server 2005 I can use to get the server's IP or name?
10 Answers
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How do I view the SQL generated by the Entity Framework?
How do I view the SQL generated by entity framework ?
22 Answers
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SQL Server dynamic PIVOT query?
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Dynamic SQL PIVOT:
create table temp
(
date datetime,
category varchar(3),
amount money
)
insert into temp values ('1/1/2012', 'ABC', 1000.00)
insert into temp values ('2/1/2012', 'DEF', 500.00)
insert into temp values ...
Is there any difference between “!=” and “” in Oracle Sql?
...r all other DBMS - most of them support both styles):
Here is the current SQL reference: https://docs.oracle.com/database/121/SQLRF/conditions002.htm#CJAGAABC
The SQL standard only defines a single operator for "not equals" and that is <>
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Search for one value in any column of any table inside a database
...a UID of the type char(64) ) inside any column of any table inside one MS SQL Server database?
7 Answers
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How to remove not null constraint in sql server using query
I am trying to remove not null constraint in sql server 2008 without losing data.
4 Answers
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SQL Server. How to refresh the intellisense? [duplicate]
I'm new to SQL Server, so this is probably an easy fix. In SQL Server 2008 R2, I've just imported a new data table and/or renamed fields in an existing table (it happens either way). When I start to write some SQL, the intellisense doesn't recognize the new field names and starts underlining every...
SQL中使用update inner join和delete inner join；Oracle delete join替代...
SQL中使用update inner join和delete inner join；Oracle delete join替代方案UpdateUpdate XXX set XXX where 这种写法大家肯定都知道，才发现update和delete居然支持inner join的update方式，这个在表间关联来...Update
Update XXX set XXX where 这种写法大家肯定都...
SQL left join vs multiple tables on FROM line?
Most SQL dialects accept both the following queries:
11 Answers
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