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Is there any performance gain in indexing a boolean field?
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It depends on the actual queries and the selectivity of the index/query combination.
Case A: condition WHERE isok = 1 and nothing else there:
SELECT *
FROM tableX
WHERE isok = 1
If the index is selective enough (say you have 1M rows and only 1k have isok = 1), ...
How do you copy the contents of an array to a std::vector in C++ without looping?
...ven when a function expects c-style arrays you can use vectors:
vector<char> v(50); // Ensure there's enough space
strcpy(&v[0], "prefer vectors to c arrays");
Hope that helps someone out there!
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Tools to generate database tables diagram with Postgresql? [closed]
...rse engineer") an existing DB schema (via JDBC) and make a diagram of some selected tables.
Shortcut to Apply a Formula to an Entire Column in Excel [closed]
If I select a cell containing a formula, I know I can drag the little box in the right-hand corner downwards to apply the formula to more cells of the column. Unfortunately, I need to do this for 300,000 rows!
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jQuery - Detecting if a file has been selected in the file input [duplicate]
...lt;/script>
You may want to add IDs to your input and span so you can select based on those to be specific to the elements you are concerned with and not other file inputs or spans in the DOM.
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Debugging Scala code with simple-build-tool (sbt) and IntelliJ
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Enter whatever name you want, and click the "Run SBT Action" checkbox and select the SBT Action jetty-run from the [...]
Create a debug configuration for remote debugging
Go to Run > Edit Configurations
Click the [+] icon and choose Remote
Enter whatever name you want and copy the line -Xdebu...
Convert Datetime column from UTC to local time in select statement
I'm doing a few SQL select queries and would like to convert my UTC datetime column into local time to be displayed as local time in my query results. Note, I am NOT looking to do this conversion via code but rather when I am doing manual and random SQL queries against my databases.
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Delete branches in Bitbucket
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in Bitbucket go to branches in left hand side menu.
Select your branch you want to delete.
Go to action column, click on three dots (...) and select delete.
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How can I select random files from a directory in bash?
I have a directory with about 2000 files. How can I select a random sample of N files through using either a bash script or a list of piped commands?
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Understanding colors on Android (six characters)
...ed as RGB or ARGB.
http://en.wikipedia.org/wiki/ARGB
In RGB you have two characters for every color (red, green, blue), and in ARGB you have two additional chars for the alpha channel.
So, if you have 8 characters, it's ARGB, with the first two characters specifying the alpha channel. If you remo...