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SQL WHERE condition is not equal to?
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You can do like this
DELETE FROM table WHERE id NOT IN ( 2 )
OR
DELETE FROM table WHERE id <> 2
As @Frank Schmitt noted, you might want to be careful about the NULL values too. If you want to delete everything which is not 2(including the NULLs...
Database development mistakes made by application developers [closed]
... auto-incrementing fields (SQL Server, MySQL, others) or sequences (most notably Oracle).
In my opinion you should always use surrogate keys. This issue has come up in these questions:
How do you like your primary keys?
What's the best practice for primary keys in tables?
Which format of primary...
How does one reorder columns in a data frame?
...ec]
return(data)
}
Now the OP's request becomes as simple as this:
table <- data.frame(Time=c(1,2), In=c(2,3), Out=c(3,4), Files=c(4,5))
table
## Time In Out Files
##1 1 2 3 4
##2 2 3 4 5
arrange.vars(table, c("Out"=2))
## Time Out In Files
##1 1 3 2 4
##2...
Permanently Set Postgresql Schema Path
... set schema path in Postgres so that I don't every time specify schema dot table e.g. schema2.table .
Set schema path:
3 ...
How to stop text from taking up more than 1 line?
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Note: this only works on block elements. If you need to do this to table cells (for example) you need to put a div inside the table cell as table cells have display table-cell not block.
As of CSS3, this is supported for table cells as well.
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When do I need to use Begin / End Blocks and the Go keyword in SQL Server?
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GO is like the end of a script.
You could have multiple CREATE TABLE statements, separated by GO. It's a way of isolating one part of the script from another, but submitting it all in one block.
BEGIN and END are just like { and } in C/++/#, Java, etc.
They bound a logical block of ...
Why malloc+memset is slower than calloc?
...n parts here: your program, the standard library, the kernel, and the page tables. You already know your program, so...
Memory allocators like malloc() and calloc() are mostly there to take small allocations (anything from 1 byte to 100s of KB) and group them into larger pools of memory. For exam...
What is the purpose of Order By 1 in SQL select statement?
...relation names are allowed in the OREDER BY clause because, in theory, the table correlation names are out of scope i.e. should be ORDER BY PAYMENT_DATE;. Of course, not all SQL implementations conform to Standards.
– onedaywhen
Aug 10 '10 at 7:17
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Datatables - Search Box outside datatable
I'm using DataTables ( datatables.net ) and I would like my search box to be outside of the table (for example in my header div).
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Oracle Differences between NVL and Coalesce
...n search contains comparison of nvl result with an indexed column.
create table tt(a, b) as
select level, mod(level,10)
from dual
connect by level<=1e4;
alter table tt add constraint ix_tt_a primary key(a);
create index ix_tt_b on tt(b);
explain plan for
select * from tt
where a=nvl(:1,a)
an...