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How to select rows from a DataFrame based on column values?
How to select rows from a DataFrame based on values in some column in Pandas?
10 Answers
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Why does JPA have a @Transient annotation?
...he transient keyword, that field will not be serialized when the object is converted to a byte stream. Furthermore, since JPA treats fields marked with the transient keyword as having the @Transient annotation, the field will not be persisted by JPA either.
On the other hand, fields annotated @Tra...
Can we make unsigned byte in Java
I am trying to convert a signed byte in unsigned. The problem is the data I am receiving is unsigned and Java does not support unsigned byte, so when it reads the data it treats it as signed.
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How to use GROUP BY to concatenate strings in MySQL?
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SELECT id, GROUP_CONCAT(name SEPARATOR ' ') FROM table GROUP BY id;
http://dev.mysql.com/doc/refman/5.0/en/group-by-functions.html#function_group-concat
From the link above, GROUP_CONCAT: This function returns a string res...
Viewing complete strings while debugging in Eclipse
...ck on Details pane (the section where the string content is displayed) and select "Max Length..." popup menu. The same length applies to expression inspector popup and few other places.
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SQL Group By with an Order By
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In all versions of MySQL, simply alias the aggregate in the SELECT list, and order by the alias:
SELECT COUNT(id) AS theCount, `Tag` from `images-tags`
GROUP BY `Tag`
ORDER BY theCount DESC
LIMIT 20
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Where is the itoa function in Linux?
itoa() is a really handy function to convert a number to a string. Linux does not seem to have itoa() , is there an equivalent function or do I have to use sprintf(str, "%d", num) ?
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Unable to export Apple production push SSL certificate in .p12 format
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Turns out all you have to do is select "My Certificates" on the left panel and it enables the .p12 option.
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No compiler is provided in this environment. Perhaps you are running on a JRE rather than a JDK?
...and check your installed JREs. You should have an entry with a JDK there.
Select the Execution Env as show below. Click OK
Then Right-Click on your Project -> Maven -> Update Project
Additionally, you may have to change Maven JRE (see @jlars62 answer) which is as follows. Goto Run -> Ru...
How do I find out my MySQL URL, host, port and username?
...If you're already logged into the command line client try this:
mysql> select user();
It will output something similar to this:
+----------------+
| user() |
+----------------+
| root@localhost |
+----------------+
1 row in set (0.41 sec)
In my example above, I was logged in as root...