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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 to take backup of a single table in a MySQL database?
...
You can use easily to dump selected tables using MYSQLWorkbench tool ,individually or group of tables at one dump then import it as follow: also u can add host information if u are running it in your local by adding -h IP.ADDRESS.NUMBER after-u usernam...
List all base classes in a hierarchy of given class?
...ass Foo (whether it is a new-style class or not), how do you generate all the base classes - anywhere in the inheritance hierarchy - it issubclass of?
...
What is the string concatenation operator in Oracle?
...
It is ||, for example:
select 'Mr ' || ename from emp;
The only "interesting" feature I can think of is that 'x' || null returns 'x', not null as you might perhaps expect.
...
Copy / Put text on the clipboard with FireFox, Safari and Chrome
...browsers using
document.execCommand('copy');
This will copy currently selected text. You can select a textArea or input field using
document.getElementById('myText').select();
To invisibly copy text you can quickly generate a textArea, modify the text in the box, select it, copy it, and then...
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...
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 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 ...
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
add a comment
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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...