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What's the difference between RANK() and DENSE_RANK() functions in oracle?
...SE_RANK() functions? How to find out nth salary in the following emptbl table?
10 Answers
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SqlException from Entity Framework - New transaction is not allowed because there are other threads
...for performance for large datasets? If you have a millions records in the table. ToList() will suck them all into memory. I'm running into this very problem and was wondering whether the following would be feasible a)Detach the entity b)Create a new ObjectContext and attach the detached entity to i...
A simple explanation of Naive Bayes Classification
...
I realize that this is an old question, with an established answer. The reason I'm posting is that is the accepted answer has many elements of k-NN (k-nearest neighbors), a different algorithm.
Both k-NN and NaiveBayes are classification algorithms. Conceptually, k-NN uses...
How to get multiple selected values of select box in php?
...t;form id="form1" name="form1" method="get" action="display.php">
<table width="300" border="1">
<tr>
<td><label>Multiple Selection </label>&nbsp;</td>
<td><select name="select2[]" size="3" multiple="multiple" tabindex="1">
...
PHP: Convert any string to UTF-8 without knowing the original character set, or at least try
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Check to make sure the collation you have defined on the table/column is UTF-8 also.
– Alexey Gerasimov
Nov 15 '11 at 12:33
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Versioning SQL Server database
...N to N+1. (These go in your version control system.) A _version_history_ table, something like
create table VersionHistory (
Version int primary key,
UpgradeStart datetime not null,
UpgradeEnd datetime
);
gets a new entry every time an upgrade script runs which corresponds to th...
Adding an onclick function to go to url in JavaScript?
... 2) want to wait until it completely loads 3) so that, that web page has a table from which I need to extract all the rows. I can able to perform step 1 and if I am on already loaded website then in console I am able to extract table rows (in javascript code). But, when I am trying to write code se...
What's the difference between using INDEX vs KEY in MySQL?
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There's no difference. They are synonyms.
From the CREATE TABLE manual entry:
KEY is normally a synonym for INDEX. The key attribute PRIMARY KEY can
also be specified as just KEY when given in a column definition. This was
implemented for compatibility with other database sy...
Django templates: verbose version of a choice
...n by Noah to be more universal in dealing with data and field types:
<table>
{% for item in query %}
<tr>
{% for field in fields %}
<td>{{item|human_readable:field}}</td>
{% endfor %}
</tr>
{% endfor %}
</table>
Here's the c...
How to get a string after a specific substring?
...test time is marked with [...] and <...> marks the worst.
The above table is produced by a comprehensive time trial for all three options, produced below. I ran the tests on Python 3.7.4 on a 2017 model 15" Macbook Pro with 2.9 GHz Intel Core i7 and 16 GB ram.
This script generates random se...