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Sort rows in data.table in decreasing order on string key `order(-x,v)` gives error on data.table 1.
Let's say I have the following data.table in R :
3 Answers
3
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SQL update fields of one table from fields of another one
I have two tables:
7 Answers
7
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SQL Server SELECT INTO @variable?
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You cannot SELECT .. INTO .. a TABLE VARIABLE. The best you can do is create it first, then insert into it. Your 2nd snippet has to be
DECLARE @TempCustomer TABLE
(
CustomerId uniqueidentifier,
FirstName nvarchar(100),
LastName nvarchar(100),
...
How do I change db schema to dbo
I imported a bunch of tables from an old sql server (2000) to my 2008 database. All the imported tables are prefixed with my username, for example: jonathan.MovieData . In the table properties it lists jonathan as the db schema. When I write stored procedures I now have to include jonathan....
Is there a performance difference between CTE , Sub-Query, Temporary Table or Table Variable?
...o use query hints, restructure the query, update statistics, use temporary tables, add indexes, and so on to get better performance.
As for your question. The performance of CTEs and subqueries should, in theory, be the same since both provide the same information to the query optimizer. One diff...
Difference between natural join and inner join
...INNER JOIN and NATURAL JOIN is the number of columns returned.
Consider:
TableA TableB
+------------+----------+ +--------------------+
|Column1 | Column2 | |Column1 | Column3 |
+-----------------------+ +--------------------+
| 1 ...
Django South - table already exists
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since you already have the tables created in the database, you just need to run the initial migration as fake
./manage.py migrate myapp --fake
make sure that the schema of models is same as schema of tables in database.
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Best practices for in-app database migration for Sqlite
...anges aren't committed.
For making schema changes, sqlite supports "ALTER TABLE" syntax for certain operations (renaming the table or adding a column). This is an easy way to update existing tables in-place. See the documentation here: http://www.sqlite.org/lang_altertable.html. For deleting col...
Include headers when using SELECT INTO OUTFILE?
...e2', 'ColName3'
UNION ALL
SELECT ColName1, ColName2, ColName3
FROM YourTable
INTO OUTFILE '/path/outfile'
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Unable to update the EntitySet - because it has a DefiningQuery and no element exis
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Entity Set is mapped from Database view
A custom Database query
Database table doesn't have a primary key
After doing so, you may still need to update in the Entity Framework designer (or alternatively delete the entity and then add it) before you stop getting the error.
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