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Difference between a theta join, equijoin and natural join
...uijoin will also remove the equality column if they have same name in both tables.
– Vishal R
Nov 13 '14 at 3:42
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Best way to center a on a page vertically and horizontally? [duplicate]
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@FlashThunder you suggest tables for non-table data, aren't you?
– Vladimir Starkov
Jan 10 '15 at 3:17
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When to use MyISAM and InnoDB? [duplicate]
...s better for beginners. No worries about the foreign relationships between tables.
Faster than InnoDB on the whole as a result of the simpler structure thus much less costs of server resources. -- Mostly no longer true.
Full-text indexing. -- InnoDB has it now
Especially good for read-intensive (se...
Remove all spaces from a string in SQL Server
... trim() or worry about multiple spaces for either char or varchar:
create table #t (
c char(8),
v varchar(8))
insert #t (c, v) values
('a a' , 'a a' ),
('a a ' , 'a a ' ),
(' a a' , ' a a' ),
(' a a ', ' a a ')
select
'"' + c + '"' [IN], '"' + replac...
In SQL, what's the difference between count(column) and count(*)?
...column) does not
[edit] added this code so that people can run it
create table #bla(id int,id2 int)
insert #bla values(null,null)
insert #bla values(1,null)
insert #bla values(null,1)
insert #bla values(1,null)
insert #bla values(null,1)
insert #bla values(1,null)
insert #bla values(null,null)
se...
What are best practices for multi-language database design? [closed]
...hat is the best way to create multi-language database? To create localized table for every table is making design and querying complex, in other case to add column for each language is simple but not dynamic, please help me to understand what is the best choose for enterprise applications
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Why do you create a View in a database?
...ews can hide complexity
If you have a query that requires joining several tables, or has complex logic or calculations, you can code all that logic into a view, then select from the view just like you would a table.
2. Views can be used as a security mechanism
A view can select certain columns an...
Ordering by specific field value first
I have a table with 3 columns:
8 Answers
8
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SQL statement to get column type
Is there a SQL statement that can return the type of a column in a table?
22 Answers
2...
Removing a model in rails (reverse of “rails g model Title…”)
...oy' on that model, it will delete the migration file, but not the database table. So before run
bundle exec rake db:rollback
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