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Count the occurrences of DISTINCT values
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SELECT name,COUNT(*) as count
FROM tablename
GROUP BY name
ORDER BY count DESC;
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Replace input type=file by an image
... be updated with the filename or at least a message that the file has been selected successfully. The user has no visual input on what happened after he selected the file. Could this be done please? Perhaps change to a different image, when a file is chosen?
– JoaMika
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How to capitalize the first letter of word in a string using Java?
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Now output will have what you want. Check that your input is at least one character long before using this, otherwise you'll get an exception.
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How to remove the first character of string in PHP?
How to use PHP , Remove the first character :
13 Answers
13
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MySQL CONCAT returns NULL if any field contain NULL
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convert the NULL values with empty string by wrapping it in COALESCE
SELECT CONCAT(COALESCE(`affiliate_name`,''),'-',COALESCE(`model`,''),'-',COALESCE(`ip`,''),'-',COALESCE(`os_type`,''),'-',COALESCE(`os_version`,'')) AS device_name
FROM devices
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Should I commit or rollback a read transaction?
... I create a temp table, populate it with ids, join it with a data table to select the data that goes with the ids, then delete the temp table. I'm really just reading data, and I don't care what happens to the temp table, since it's temporary... but from a performance perspective, would it be more ...
Default value of 'boolean' and 'Boolean' in Java
...ull. Primitives have different default values:
boolean -> false
byte, char, short, int, long -> 0
float, double -> 0.0
Note (2): void has a wrapper Void which also has a default of null and is it's only possible value (without using hacks).
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How to do a join in linq to sql with method syntax?
...eOtherClass
on sc.Property1 equals soc.Property2
select new { SomeClass = sc, SomeOtherClass = soc };
Would be equivalent to:
var result = enumerableOfSomeClass
.Join(enumerableOfSomeOtherClass,
sc => sc.Property1,
soc => soc.Property2,
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How to select rows with one or more nulls from a pandas DataFrame without listing columns explicitly
... 0.0 NaN 0.0
3 0.0 1.0 2.0 3.0
4 NaN 0.0 NaN NaN
If you want to select the rows that have two or more columns with null value, you run the following:
>>> qty_of_nuls = 2
>>> df.iloc[df[(df.isnull().sum(axis=1) >=qty_of_nuls)].index]
0 1 2 3
1 0.0 NaN 0...
Java String remove all non numeric characters
Trying to remove all letters and characters that are not 0-9 and a period. I'm using Character.isDigit() but it also removes decimal, how can I also keep the decimal?
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