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Strings as Primary Keys in SQL Database [closed]
I am not very familiar with databases and the theories behind how they work. Is it any slower from a performance standpoint (inserting/updating/querying) to use Strings for Primary Keys than integers?
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Git: can I suppress listing of 'modified content'/dirty submodule entries in status, diff, etc?
...module within the .gitmodules file.
Just today I encountered this problem and immediately wrote an article in my blog about it after finding a solution: How to ignore changes in git submodules
The gist of it:
Once you added a submodule there will be a file named .gitmodules in the root of your...
What is a vertical tab?
... the default vertical size being one line. I have tested with perl "\013" and the same output occurs. This could be used to do line feed without a carriage return on devices with convert linefeed to carriage-return + linefeed.
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Type definition in object literal in TypeScript
...has methods as well as properties? Since the class doesn't get initialized and we only assign properties, calling a method on the class will cause a null exception. Basically, the object we create only 'acts' as the class because we assign its type, but it is not actually an instance of that class. ...
How can you determine how much disk space a particular MySQL table is taking up?
...length) tablesize
FROM information_schema.tables
WHERE table_schema='mydb' and table_name='mytable';
KILOBYTES
SELECT (data_length+index_length)/power(1024,1) tablesize_kb
FROM information_schema.tables
WHERE table_schema='mydb' and table_name='mytable';
MEGABYTES
SELECT (data_length+index_len...
Best practice to validate null and empty collection in Java
I want to verify whether a collection is empty and null . Could anyone please let me know the best practice.
9 Answers
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Disable HttpClient logging
...egration test suite. The default logging for HttpClient is extremely noisy and I can't seem to turn it off. I've tried following the instructions here but none of them make any difference.
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MySQL Cannot drop index needed in a foreign key constraint
...n key might not be as obvious. To find all foreign keys related to a table and column, you can use this query: dba.stackexchange.com/questions/102371/…
– charlax
Jun 12 '19 at 14:54
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Getting rid of \n when using .readlines() [duplicate]
...of data. So tab-separated values is a circumstance where that would be bad and if stated that way, this answer would never be my recommendation.
– hughdbrown
Jun 3 '18 at 19:18
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How to query as GROUP BY in django?
...ignation, COUNT(designation) AS dcount
FROM members GROUP BY designation
and the output would be of the form
[{'designation': 'Salesman', 'dcount': 2},
{'designation': 'Manager', 'dcount': 2}]
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