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What's the best practice for primary keys in tables?
...having artifical keys, nor of never having them. I would decide on a case-by-case basis, for example:
US States: I'd go for state_code ('TX' for Texas etc.), rather than state_id=1 for Texas
Employees: I'd usually create an artifical employee_id, because it's hard to find anything else that works...
How can one use multi threading in PHP applications
...f ($g->join()) {
printf(" and %f seconds to finish receiving %d bytes\n", microtime(true) - $t, strlen($g->data));
} else
printf(" and %f seconds to finish, request failed\n", microtime(true) - $t);
}
...
How to remove constraints from my MySQL table?
...ing the foreign key in the first place, then it will not be removed simply by dropping the foreign key.
– Rich Harding
Nov 21 '17 at 21:33
add a comment
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How to remove a column from an existing table?
...t generally speaking this is not so trivial.
If this column is referenced by other tables then you need to figure out what to do with other tables/columns. One option is to remove foreign keys and keep referenced data in other tables.
Another option is to find all referencing columns and remove th...
Unable to open project… cannot be opened because the project file cannot be parsed
...had a merge conflict in the PBXGroup section (whose beginning is indicated by a block comment like this: /* Begin PBXGroup section */) of the project.pbxproj file. However, the problem I encountered can occur in other places in the project.pbxproj file as well.
Below is a simplification of the merg...
Unioning two tables with different number of columns
...u just replace NULL with some value. This also worked when used with groupby.
– Saurabh Jain
Feb 27 at 6:27
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How to add multiple objects to ManyToMany relationship at once in Django ?
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Any way to do this by value (ex. id)? Sometimes you don't have a list of objects but a list of object values (i.e. id's)? Rather than looping through and grabbing all objects into another list...
– DannyMoshe
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How can I count text lines inside an DOM element? Can I?
...u can retrieve the div's height using:
var divHeight = document.getElementById('content').offsetHeight;
And divide by the font line height:
document.getElementById('content').style.lineHeight;
Or to get the line height if it hasn't been explicitly set:
var element = document.getElementById('c...
Input placeholders for Internet Explorer
...
Best one in my experience is https://github.com/mathiasbynens/jquery-placeholder (recommended by html5please.com). http://afarkas.github.com/webshim/demos/index.html also has a good solution among its much more extensive library of polyfills.
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How to remove selected commit log entries from a Git repository while keeping their changes?
...n the above command. It launches your $EDITOR.
Replace pick before C and D by squash. It will meld C and D into B. If you want to delete a commit then just delete its line.
If you are lost, type:
$ git rebase --abort
s...