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What does SQL clause “GROUP BY 1” mean?
...
SELECT account_id, open_emp_id
^^^^ ^^^^
1 2
FROM account
GROUP BY 1;
In above query GROUP BY 1 refers to the first column in select statement which is
account_id.
You also can speci...
How to check existence of user-define table type in SQL Server 2008?
...y. You can't use OBJECT_ID to search for a table type by name -- check out SELECT name FROM sys.objects WHERE type = 'TT'
– NReilingh
Nov 29 '15 at 9:17
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How to list all the available keyspaces in Cassandra?
...keyspace in the system schema using the SQL query
below is the command.
SELECT * FROM system_schema.keyspaces;
Hope this will answer your question...
You can go through the explanation on understanding and creating the keyspaces from below resources.
Documentation:
https://docs.datastax.co...
How do I write good/correct package __init__.py files
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__all__ is very good - it helps guide import statements without automatically importing modules
http://docs.python.org/tutorial/modules.html#importing-from-a-package
using __all__ and import * is redundant, only __all__ is nee...
compilation warning: no rule to process file for architecture i386
...w:-
Some .md, .mdown .h files are included in the Compile Sources
Step 1) Select Project Navigator
Step 2) Select your project
Step 3) Select your targetStep
Step 4) Select Build PhasesStep
Step 5) Move files which we don't want the compiler to process from Compile Sources to Copy Bundle Resource...
COUNT DISTINCT with CONDITIONS
...
You can try this:
select
count(distinct tag) as tag_count,
count(distinct (case when entryId > 0 then tag end)) as positive_tag_count
from
your_table_name;
The first count(distinct...) is easy.
The second one, looks somewhat complex...
T-SQL CASE Clause: How to specify WHEN NULL
...
Given your query you can also do this:
SELECT first_name + ' ' + ISNULL(last_name, '') AS Name FROM dbo.person
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How to use android emulator for testing bluetooth application?
... virtual machine set the network adapter to 'Bridged'. ·
Start the VM and select 'Live CD VESA' at boot.
Now you need to find out the IP of this VM. Go to terminal in VM (use Alt+F1
& Alt+F7 to toggle) and use the netcfg command to find this.
Now you need open a command prompt and go to your ...
INNER JOIN vs LEFT JOIN performance in SQL Server
...(ID, Name) VALUES (4, 'Four')
INSERT #Test2 (ID, Name) VALUES (5, 'Five')
SELECT *
FROM #Test1 t1
INNER JOIN #Test2 t2
ON t2.Name = t1.Name
SELECT *
FROM #Test1 t1
LEFT JOIN #Test2 t2
ON t2.Name = t1.Name
DROP TABLE #Test1
DROP TABLE #Test2
If you run this and view the execution plan, you'll se...
How to show SQL queries run in the Rails console?
...ecord::Relation’s to_sql method:
User.where(:id => 3).to_sql
#=> "SELECT \"users\".* FROM \"users\" WHERE \"users\".\"id\" = 3"
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follo...