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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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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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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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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...
How to compare two Dates without the time portion?
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I don't think that would work, even if converting to Strings was a good idea. The == operator doesn't necessarily return true for equivalent Strings (use equals()). You certainly can't use the other comparison operators you mentioned, either.
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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...
What is the difference between ExecuteScalar, ExecuteReader and ExecuteNonQuery?
... then the result is the first column of the first row. An example might be SELECT @@IDENTITY AS 'Identity'.
ExecuteReader is used for any result set with multiple rows/columns (e.g., SELECT col1, col2 from sometable).
ExecuteNonQuery is typically used for SQL statements without results (e.g., UPDATE...
Set time to 00:00:00
...Use *java.time* instead.
.toInstant() // Convert this moment in UTC from the legacy class `Date` to the modern class `Instant`.
.atZone( ZoneId.of( "Africa/Tunis" ) ) // Adjust from UTC to the wall-clock time used by the people of a particular region (a time...
How to check if field is null or empty in MySQL?
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Either use
SELECT IF(field1 IS NULL or field1 = '', 'empty', field1) as field1
from tablename
or
SELECT case when field1 IS NULL or field1 = ''
then 'empty'
else field1
end as field1
from tablename
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How to pick an image from gallery (SD Card) for my app?
...EQ_CODE_PICK_IMAGE:
if(resultCode == RESULT_OK){
Uri selectedImage = imageReturnedIntent.getData();
String[] filePathColumn = {MediaStore.Images.Media.DATA};
Cursor cursor = getContentResolver().query(
selectedImage, fileP...