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Difference between partition key, composite key and clustering key in Cassandra?
...KEY:
insert into stackoverflow_simple (key, data) VALUES ('han', 'solo');
select * from stackoverflow_simple where key='han';
table content
key | data
----+------
han | solo
COMPOSITE/COMPOUND KEY can retrieve "wide rows" (i.e. you can query by just the partition key, even if you have clusteri...
How to add “on delete cascade” constraints?
...hy until you see "Constraints"), or you can query the information schema.
select *
from information_schema.key_column_usage
where position_in_unique_constraint is not null
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Storing time-series data, relational or non?
...evation.
Correction
It is not "filtering out the un-needed data"; it is selecting only the needed data. Yes, of course, if you have an Index to support the columns identified in the WHERE clause, it is very fast, and the query does not depend on the size of the table (grabbing 1,000 rows from a ...
How do I copy items from list to list without foreach?
...single property to another list is needed:
targetList.AddRange(sourceList.Select(i => i.NeededProperty));
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LIKE vs CONTAINS on SQL Server
...o will always require a full table scan.
The CONTAINS query should be:
SELECT * FROM table WHERE CONTAINS(Column, 'test');
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How to change Android version and code version number?
...Ctrl+Alt+Shift+S in android studio or go to File > Project Structure...
Select app on left side and select falvors tab on right side on default config change version code , name and etc...
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Read logcat programmatically within application
... // log level: ALL
sCommand.add("*:S"); // ignore logs which are not selected
Process process = new ProcessBuilder().command(sCommand).start();
BufferedReader bufferedReader = new BufferedReader(
new InputStreamReader(process.getInputStream()));
LogCapture mLogCapt...
File Upload ASP.NET MVC 3.0
...esult Index(HttpPostedFileBase file)
{
// Verify that the user selected a file
if (file != null && file.ContentLength > 0)
{
// extract only the filename
var fileName = Path.GetFileName(file.FileName);
// store the file insi...
How can I merge two hashes without overwritten duplicate keys in Ruby?
... and defaults without overwriting the destination hash, you may check with select if the key is already present in the destination hash. Here's the pure Ruby solution without Rails:
options = { "a" => 100, "b" => 200 }
defaults = { "b" => 254, "c" => 300 }
options.merge!(defaults.selec...
AppSettings get value from .config file
...iguration
Go to your Solution Explorer and right click on References and select Add reference. Select the Assemblies tab and search for Configuration.
Here is an example of my App.config:
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<startup>
<suppo...