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Deleting all rows from Cassandra cql table [duplicate]
Is there a command to all the rows present in a cql table in cassandra like the one in sql?
1 Answer
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git discard all changes and pull from upstream
...anch on my repo, which is master, and I completely messed it up, so I basically need to start over from the upstream. I think init will do the job, but is there an easier way?
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How to view corresponding SQL query of the Django ORM's queryset?
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You also can use python logging to log all queries generated by Django. Just add this to your settings file.
LOGGING = {
'disable_existing_loggers': False,
'version': 1,
'handlers': {
'console': {
# logging handler that outputs log...
What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
The "N+1 selects problem" is generally stated as a problem in Object-Relational mapping (ORM) discussions, and I understand that it has something to do with having to make a lot of database queries for something that seems simple in the object world.
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Get current directory name (without full path) in a Bash script
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No need for basename, and especially no need for a subshell running pwd (which adds an extra, and expensive, fork operation); the shell can do this internally using parameter expansion:
result=${PWD##*/} # to assign to a variable
printf '%s\n' "$...
ERROR 1130 (HY000): Host '' is not allowed to connect to this MySQL server [duplicate]
...vileges:
CREATE USER 'root'@'ip_address' IDENTIFIED BY 'some_pass';
GRANT ALL PRIVILEGES ON *.* TO 'root'@'ip_address';
If you see %, well then, there's another problem altogether as that is "any remote source". If however you do want any/all systems to connect via root, use the % wildcard to gra...
How to concatenate a std::string and an int?
I thought this would be really simple but it's presenting some difficulties. If I have
23 Answers
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How to re-create database for Entity Framework?
...ed, if so, right click and delete.
2 )Go to Solution Explorer, click show All Files icon.
3) Go to App_Data, right click and delete all ".mdf" files for this project.
4) Delete Migrations folder by right click and delete.
5) Go to SQL Server Management Studio, make sure the DB for this project i...
Listing only directories using ls in Bash?
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*/ is a pattern that matches all of the subdirectories in the current directory (* would match all files and subdirectories; the / restricts it to directories). Similarly, to list all subdirectories under /home/alice/Documents, use ls -d /home/alice/Docu...
Detecting WPF Validation Errors
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This post was extremely helpful. Thanks to all who contributed. Here is a LINQ version that you will either love or hate.
private void CanExecute(object sender, CanExecuteRoutedEventArgs e)
{
e.CanExecute = IsValid(sender as DependencyObject);
}
private bool IsV...