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Rename column SQL Server 2008
I am using SQL Server 2008 and Navicat. I need to rename a column in a table using SQL.
11 Answers
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Random record in ActiveRecord
I'm in need of getting a random record from a table via ActiveRecord. I've followed the example from Jamis Buck from 2006 .
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MySql server startup error 'The server quit without updating PID file '
...efix mysql)" --datadir=/usr/local/var/mysql --tmpdir=/tmp
To set up base tables in another folder, or use a different user to run
mysqld, view the help for mysqld_install_db:
mysql_install_db --help
and view the MySQL documentation:
http://dev.mysql.com/doc/refman/5.5/en/mysql-install-db.html...
SQL Server add auto increment primary key to existing table
As the title, I have an existing table which is already populated with 150000 records. I have added an Id column (which is currently null).
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How to check if a column exists in a SQL Server table?
...HERE Name = N'columnName'
AND Object_ID = Object_ID(N'schemaName.tableName'))
BEGIN
-- Column Exists
END
Martin Smith's version is shorter:
IF COL_LENGTH('schemaName.tableName', 'columnName') IS NOT NULL
BEGIN
-- Column Exists
END
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Can I add a UNIQUE constraint to a PostgreSQL table, after it's already created?
I have the following table:
4 Answers
4
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Cast Int to enum in Java
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@Tarrasch as arrays are mutable, values() must return a copy of the array of elements just in case you happen to change it. Creating this copy each time is relatively expensive.
– Peter Lawrey
Dec 4 '12 at 8:44
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Changing the size of a column referenced by a schema-bound view in SQL Server
...SDN:
SCHEMABINDING
Binds the view to the schema of the underlying table or tables. When
SCHEMABINDING is specified, the base
table or tables cannot be modified in
a way that would affect the view
definition. The view definition itself
must first be modified or dropped to
remove ...
INNER JOIN ON vs WHERE clause
...It is generally considered more readable, especially when you join lots of tables.
It can also be easily replaced with an OUTER JOIN whenever a need arises.
The WHERE syntax is more relational model oriented.
A result of two tables JOINed is a cartesian product of the tables to which a filter is ...
How to join (merge) data frames (inner, outer, left, right)
...f performance is a major issue for you, you should also look into the data.table package - that's a whole new set of join syntax, but it's radically faster than anything we're talking about here.
– Matt Parker
Feb 12 '13 at 16:22
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