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Error 1022 - Can't write; duplicate key in table
...ou can not have the same foreign key names in the database tables.
Check all your tables and all your foreign keys and avoid having two foreign keys with the same exact name.
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Manipulating an Access database from Java without ODBC
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UCanAccess is a pure Java JDBC driver that allows us to read from and write to Access databases without using ODBC. It uses two other packages, Jackcess and HSQLDB, to perform these tasks. The following is a brief overview of how to get it set up.
Option 1: Using...
How to convert a SVG to a PNG with ImageMagick?
... to convert it into a PNG, then I get a 16x16 pixel PNG which is way too small:
18 Answers
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How do I do an OR filter in a Django query?
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@alexis: you could also do Item.objects.filter(creator__in=creators), for example.
– Kevin London
Dec 9 '14 at 23:11
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Changing selection in a select with the Chosen plugin
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From the "Updating Chosen Dynamically" section in the docs: You need to trigger the 'chosen:updated' event on the field
$(document).ready(function() {
$('select').chosen();
$('button').click(function() {
$('select').val(2);
$('sel...
Display names of all constraints for a table in Oracle SQL
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You need to query the data dictionary, specifically the USER_CONS_COLUMNS view to see the table columns and corresponding constraints:
SELECT *
FROM user_cons_columns
WHERE table_name = '<your table name>';
FYI, unless you specifically created your table with ...
Converting NSString to NSDate (and back again)
...String = @"01-02-2010";
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:@"dd-MM-yyyy"];
NSDate *dateFromString = [dateFormatter dateFromString:dateString];
NSDate convert to NSString:
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[d...
Python concatenate text files
...new file. I could open each file by f = open(...) , read line by line by calling f.readline() , and write each line into that new file. It doesn't seem very "elegant" to me, especially the part where I have to read//write line by line.
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No route matches [GET] /assets
...nment. I ran RAILS_ENV=production rake assets:precompile which generated all of my assets in /public/assets. The problem is that when I start my app w/ RAILS_ENV=production rails s thin I get:
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ImportError: numpy.core.multiarray failed to import
... following command in my Mac terminal:
python -c "import numpy;print(numpy.__version__);print(numpy.__file__)";
This command gave me the version and location of numpy that I was using (turned out it was 1.6.2). I went to this location and manually replaced it with the numpy folder for 1.8, which re...