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How do DATETIME values work in SQLite?
I’m creating Android apps and need to save date/time of the creation record. The SQLite docs say, however, "SQLite does not have a storage class set aside for storing dates and/or times" and it's "capable of storing dates and times as TEXT, REAL, or INTEGER values".
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NULL values inside NOT IN clause
...t I thought were identical queries one using a not in where constraint and the other a left join . The table in the not in constraint had one null value (bad data) which caused that query to return a count of 0 records. I sort of understand why but I could use some help fully grasping the con...
How to create a directory if it doesn't exist using Node.js?
...rectory if it doesn't exist.
It should have full permission for the script and readable by others.
17 Answers
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ORA-12514 TNS:listener does not currently know of service requested in connect descriptor
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I had this issue and the fix was to make sure in tnsnames.ora the SERVICE_NAME is a valid service name in your database. To find out valid service names, you can use the following query in oracle:
select value from v$parameter where name='se...
Returning null as an int permitted with ternary operator but not if statement
...itional operator (as described in the Java Language Specification, 15.25), and moves happily on. This will generate a NullPointerException at run time, which you can confirm by trying it.
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Best way to select random rows PostgreSQL
I want a random selection of rows in PostgreSQL, I tried this:
12 Answers
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Produce a random number in a range using C#
How do I go about producing random numbers within a range?
7 Answers
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Upgrade python in a virtualenv
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Did you see this? If I haven't misunderstand that answer, you may try to create a new virtualenv on top of the old one. You just need to know which python is going to use your virtualenv (you will need to see your virtualenv version).
If your virtualenv is install...
HTML anchor link - href and onclick both?
I want to author an anchor tag that executes some JavaScript and then proceeds to go wherever the href was taking it. Invoking a function that executes my JavaScript and then sets window.location or top.location to the href location doesn't work for me.
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Simple way to calculate median with MySQL
What's the simplest (and hopefully not too slow) way to calculate the median with MySQL? I've used AVG(x) for finding the mean, but I'm having a hard time finding a simple way of calculating the median. For now, I'm returning all the rows to PHP, doing a sort, and then picking the middle row, but ...