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Hidden Features of SQL Server
...T clause allows to do this very easily - it allows access to the "virtual" tables called inserted and deleted (like in triggers):
DELETE FROM (table)
OUTPUT deleted.ID, deleted.Description
WHERE (condition)
If you're inserting values into a table which has an INT IDENTITY primary key field, with ...
Change Schema Name Of Table In SQL
I want to change schema name of table Employees in Database. In the current table Employees database schema name is dbo I want to change it to exe . How can I do it ?
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how to get last insert id after insert query in codeigniter active record
...rt query (active record style) used to insert the form fields into a MySQL table. I want to get the last auto-incremented id for the insert operation as the return value of my query but I have some problems with it.
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MySQL how to join tables on two fields
I have two tables with date and id fields. I want to join on both fields. I tried
3 Answers
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How to drop multiple columns in postgresql
I want to drop 200 columns in my table in PostgreSQL. I tried:
2 Answers
2
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Remove rows with all or some NAs (missing values) in data.frame
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If performance is a priority, use data.table and na.omit() with optional param cols=.
na.omit.data.table is the fastest on my benchmark (see below), whether for all columns or for select columns (OP question part 2).
If you don't want to use data.table, use comple...
SQL Joins Vs SQL Subqueries (Performance)?
...ies with Semijoin Transformations
Rewriting Subqueries as Joins
I have a table with 50000 elements, the result i was looking for was 739 elements.
My query at first was this:
SELECT p.id,
p.fixedId,
p.azienda_id,
p.categoria_id,
p.linea,
p.tipo,
p.nome
FROM prodotto p
WH...
Exporting data In SQL Server as INSERT INTO
I am using SQL Server 2008 Management Studio and have a table I want to migrate to a different db server.
11 Answers
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Is SQL syntax case sensitive?
...OM, WHERE, etc), but are often written in all caps. However in some setups table and column names are case-sensitive. MySQL has a configuration option to enable/disable it. Usually case-sensitive table and column names are the default on Linux MySQL and case-insensitive used to be the default on Win...
How to sort a dataframe by multiple column(s)
...ices
order from base
arrange from dplyr
setorder and setorderv from data.table
arrange from plyr
sort from taRifx
orderBy from doBy
sortData from Deducer
Most of the time you should use the dplyr or data.table solutions, unless having no-dependencies is important, in which case use base::order.
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