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MySQL “NOT IN” query
I wanted to run a simple query to throw up all the rows of Table1 where a principal column value is not present in a column in another table ( Table2 ).
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C++ - passing references to std::shared_ptr or boost::shared_ptr
...now that sp->do_something() will not blow up due to a null pointer?
It all depends what is in those '...' sections of the code. What if you call something during the first '...' that has the side-effect (somewhere in another part of the code) of clearing a shared_ptr to that same object? And wha...
Is it possible to get all arguments of a function as single object inside that function?
...t an "Object which has a length property of a non-negative Integer, and usually some indexed properties." From the mozilla link: "It is similar to an Array, but does not have any Array properties except length."
– Luke
Aug 7 '17 at 13:09
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How to truncate a foreign key constrained table?
...ata integrity.
Option 1:
Remove constraints
Perform TRUNCATE
Delete manually the rows that now have references to nowhere
Create constraints
Option 2: suggested by user447951 in their answer
SET FOREIGN_KEY_CHECKS = 0;
TRUNCATE table $table_name;
SET FOREIGN_KEY_CHECKS = 1;
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List All Redis Databases
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Or you can just run the following command and you will see all databases of the Redis instance without firing up redis-cli:
$ redis-cli INFO | grep ^db
db0:keys=1500,expires=2
db1:keys=200000,expires=1
db2:keys=350003,expires=1
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Are duplicate keys allowed in the definition of binary search trees?
...cluded. For example, the example algorithms in the MIT Algorithms book usually present examples without duplicates. It is fairly trivial to implement duplicates (either as a list at the node, or in one particular direction.)
Most (that I've seen) specify left children as <= and right children ...
Tar a directory, but don't store full absolute paths in the archive
...-C works; just for clarification I'll post 2 examples:
creation of a tarball without the full path:
full path /home/testuser/workspace/project/application.war and what we want is just project/application.war so:
tar -cvf output_filename.tar -C /home/testuser/workspace project
Note: there is a ...
Understanding MongoDB BSON Document size limit
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First off, this actually is being raised in the next version to 8MB or 16MB ... but I think to put this into perspective, Eliot from 10gen (who developed MongoDB) puts it best:
EDIT: The size has been officially 'raised' to 16MB
So, on your...
How to get instance variables in Python?
Is there a built-in method in Python to get an array of all a class' instance variables? For example, if I have this code:
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How to get RelativeLayout working with merge and include?
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This is really easier, less hardcoded, and more optimized solution than packing <include/> into another layout. Think what would you do if you would work with lists.
– teoREtik
Feb 2 '12 at ...