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Postgresql - change the size of a varchar column to lower length
I have a question about the ALTER TABLE command on a really large table (almost 30 millions rows).
One of its columns is a varchar(255) and I would like to resize it to a varchar(40) .
Basically, I would like to change my column by running the following command:
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How to create a HashMap with two keys (Key-Pair, Value)?
I have a 2D array of Integers. I want them to be put into a HashMap. But I want to access the elements from the HashMap based on Array Index. Something like:
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How can I override the OnBeforeUnload dialog and replace it with my own?
I need to warn users about unsaved changes before they leave a page (a pretty common problem).
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How do I use Assert to verify that an exception has been thrown?
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22 Answers
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How to write a:hover in inline CSS?
I have a case where I must write inline CSS code, and I want to apply a hover style on an anchor.
23 Answers
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Makefile, header dependencies
Let's say I have a makefile with the rule
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Rails migration for has_and_belongs_to_many join table
How do I do a script/generate migration to create a join table for a has_and_belongs_to_many relationship?
6 Answers
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input type=“submit” Vs button tag are they interchangeable?
input type="submit" and button tag are they interchangeable? or if there is any difference then When to use input type="submit" and when button ?
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Android Fragment lifecycle over orientation changes
Using the compatibility package to target 2.2 using Fragments.
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How to convert an integer to a string in any base?
Python allows easy creation of an integer from a string of a given base via
27 Answers
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