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Can PostgreSQL index array columns?
... If a column is an array type, will all the entered values be individually indexed?
3 Answers
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How does lucene index documents?
...ave less information in it than the older one.
In a nutshell, when lucene indexes a document it breaks it down into a number of terms. It then stores the terms in an index file where each term is associated with the documents that contain it. You could think of it as a bit like a hashtable.
Terms ...
How do I make a column unique and index it in a Ruby on Rails migration?
...ls migration script. What is the best way to do it? Also is there a way to index a column in a table?
8 Answers
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How to map with index in Ruby?
...by 1.8.7 or 1.9, you can use the fact that iterator methods like each_with_index, when called without a block, return an Enumerator object, which you can call Enumerable methods like map on. So you can do:
arr.each_with_index.map { |x,i| [x, i+2] }
In 1.8.6 you can do:
require 'enumerator'
arr.e...
How to resolve “Error: bad index – Fatal: index file corrupt” when using Git
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If the problem is with the index as the staging area for commits (i.e. .git/index), you can simply remove the index (make a backup copy if you want), and then restore index to version in the last commit:
On OSX/Linux:
rm -f .git/index
git reset
On ...
Java, How do I get current index/key in “for each” loop [duplicate]
In Java, How do I get the current index for the element in Java?
7 Answers
7
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index.php not loading by default
.../example.com/myapp/ , it says "forbidden". By default it's not loading the index.php file.
13 Answers
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Find maximum value of a column and return the corresponding row values using Pandas
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Assuming df has a unique index, this gives the row with the maximum value:
In [34]: df.loc[df['Value'].idxmax()]
Out[34]:
Country US
Place Kansas
Value 894
Name: 7
Note that idxmax returns index labels. So if the DataFrame has...
Dropping Unique constraint from MySQL table
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A unique constraint is also an index.
First use SHOW INDEX FROM tbl_name to find out the name of the index. The name of the index is stored in the column called key_name in the results of that query.
Then you can use DROP INDEX:
DROP INDEX index_name O...
Add object to ArrayList at specified index
...ider using a regular Array, initialize the capacity and put objects at the index you want.
Object[] list = new Object[10];
list[0] = object1;
list[2] = object3;
list[1] = object2;
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