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Check if a temporary table exists and delete if it exists before creating a temporary table
I am using the following code to check if the temporary table exists and drop the table if it exists before creating again. It works fine as long as I don't change the columns. If I add a column later, it will give an error saying "invalid column". Please let me know what I am doing wrong.
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Foreign key constraints: When to use ON UPDATE and ON DELETE
...ma using MySQL Workbench, which is pretty cool because you can do diagrams and it converts them :P
3 Answers
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How to use WHERE IN with Doctrine 2
...nd something that will be important to anyone running into this same issue and looking for a solution.
From the original post, the following line of code:
$qb->add('where', $qb->expr()->in('r.winner', array('?1')));
Wrapping the named parameter as an array causes the bound parameter num...
Jackson and generic type reference
...is a well-known problem with Java type erasure: T is just a type variable, and you must indicate actual class, usually as Class argument. Without such information, best that can be done is to use bounds; and plain T is roughly same as 'T extends Object'. And Jackson will then bind JSON Objects as Ma...
Rails select helper - Default selected value, how?
...g to edit your record.
You need to set the default to your existing value and then only set it to the actual default if you don't have a value. Like so:
f.select :field, options_for_select(value_array, f.object.field || default_value)
For anyone not familiar with f.object.field you always use f....
Ways to implement data versioning in MongoDB
...nt data versioning in MongoDB. (I've asked similar question regarding Cassandra . If you have any thoughts which db is better for that please share)
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Can vim monitor realtime changes to a file
...it in vim. I know I can read an opened file use tail -f sample.xml file, and when new content is written to the file, it'll also write the new content to my screen. Can I have vim automatically fill the new data when a file is updated?
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How do I find duplicates across multiple columns?
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Duplicated id for pairs name and city:
select s.id, t.*
from [stuff] s
join (
select name, city, count(*) as qty
from [stuff]
group by name, city
having count(*) > 1
) t on s.name = t.name and s.city = t.city
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Share application “link” in Android
...b link or some text.
In other words I am looking for a very direct way for android users to have my app installed.
11 Answe...
How do I get textual contents from BLOB in Oracle SQL
...ed to peek into the blob... But thanks anyway.
– Roland Tepp
May 7 '09 at 6:32
Thanks Mac, that works fine --- But wh...