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How to find all tables that have foreign keys that reference particular table.column and have values
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This solution will not only display all relations but also the constraint name, which is required in some cases (e.g. drop constraint):
SELECT
CONCAT(table_name, '.', column_name) AS 'foreign key',
CONCAT(referenced_table_name, '.', referenced_column_n...
Entity Framework Join 3 Tables
.... I have the exact scenario but the query throws an exception [the_list_of_all_return_variables]' cannot be serialized . @marcinJuraszek - Could you have a look at stackoverflow.com/questions/42453123/…
– sandiejat
Feb 25 '17 at 7:15
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SET versus SELECT when assigning variables?
...ed then SET will assign NULL, where SELECT will not make the assignment at all (so the variable will not be changed from its previous value)
As far as speed differences - there are no direct differences between SET and SELECT. However SELECT's ability to make multiple assignments in one shot does ...
Are loops really faster in reverse?
I've heard this quite a few times. Are JavaScript loops really faster when counting backward? If so, why? I've seen a few test suite examples showing that reversed loops are quicker, but I can't find any explanation as to why!
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Pairs from single list
...e=2):
it = iter(t)
return izip(*[it]*size)
When you want to pair all elements you obviously might need a fillvalue:
from itertools import izip_longest
def blockwise(t, size=2, fillvalue=None):
it = iter(t)
return izip_longest(*[it]*size, fillvalue=fillvalue)
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Why does my application spend 24% of its life doing a null check?
...t store a copy of the bytes in RAM. An important one is the L1 cache, typically 16 kilobytes for data and 16 kilobytes for instructions. Small, allowing it to be close to the execution engine. Reading bytes from the L1 cache typically takes 2 or 3 CPU cycles. Next up is the L2 cache, bigger and slow...
LINQ - Left Join, Group By, and Count
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.Count() will generate COUNT(*) which will count all the rows in that group, by the way.
– Mehrdad Afshari
Mar 29 '09 at 22:47
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How to find the nearest parent of a Git branch?
...al) are just transient labels that point to specific commits in the continually growing commit DAG. As such, the relationship between branches can vary over time, but the relationship between commits does not.
---o---1 foo
\
2---3---o bar
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MySQL foreign key constraints, cascade delete
...#2 (blue):
DELETE FROM categories WHERE (id = 2);
the DBMS will look at all the tables which have a foreign key pointing at the 'categories' table, and delete the records where the matching id is 2. Since we only defined the foreign key relationship in products_categories, you end up with this ta...
CSS to make HTML page footer stay at bottom of the page with a minimum height, but not overlap the p
...just omit the "height" and the footer will adapt to content. Not tested in all browser
– m47730
Sep 23 '15 at 7:58
Thi...