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Count the occurrences of DISTINCT values
...
SELECT name,COUNT(*) as count
FROM tablename
GROUP BY name
ORDER BY count DESC;
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How do you join on the same table, twice, in mysql?
...
you'd use another join, something along these lines:
SELECT toD.dom_url AS ToURL,
fromD.dom_url AS FromUrl,
rvw.*
FROM reviews AS rvw
LEFT JOIN domain AS toD
ON toD.Dom_ID = rvw.rev_dom_for
LEFT JOIN domain AS fromD
ON fromD.Dom_ID = rvw.rev_dom_from
ED...
Duplicate and rename Xcode project & associated folders [closed]
...ame or any associated folders at this stage.
In Xcode, rename the project. Select your project from the navigator pane (left pane). In the Utilities pane (right pane) rename your project, Accept the changes Xcode proposes.
In Xcode, rename the schemes in "Manage Schemes", also rename any targets you...
What is the difference between the remap, noremap, nnoremap and vnoremap mapping commands in Vim?
...f these sets of mappings, there is a mapping that works in normal, visual, select and operator modes (:map and :noremap), one that works in normal mode (:nmap and :nnoremap), one in visual mode (:vmap and :vnoremap) and so on.
For more guidance on this, see:
:help :map
:help :noremap
:help recursi...
How to unstash only certain files?
... relative to stash@{0})).
yucer suggests in the comments:
If you want to select manually which changes you want to apply from that file:
git difftool stash@{0}..HEAD -- <filename>
Vivek adds in the comments:
Looks like "git checkout stash@{0} -- <filename>" restores the version of t...
IN vs OR in the SQL WHERE Clause
...h are nearly instant. When the column is not indexed I got these results:
SELECT COUNT(*) FROM t_inner WHERE val IN (1000, 2000, 3000, 4000, 5000, 6000, 7000, 8000, 9000);
1 row fetched in 0.0032 (1.2679 seconds)
SELECT COUNT(*) FROM t_inner WHERE val = 1000 OR val = 2000 OR val = 3000 OR val = 40...
Generate class from database table
...eName'
declare @Result varchar(max) = 'public class ' + @TableName + '
{'
select @Result = @Result + '
public ' + ColumnType + NullableSign + ' ' + ColumnName + ' { get; set; }
'
from
(
select
replace(col.name, ' ', '_') ColumnName,
column_id ColumnId,
case typ.name...
The difference between bracket [ ] and double bracket [[ ]] for accessing the elements of a list or
...urn the ith sequential element of x.
For lists, one generally uses [[ to select any single element, whereas [ returns a list of the selected elements.
The [[ form allows only a single element to be selected using integer or character indices, whereas [ allows indexing by vectors. Note though tha...
Visual Studio Disabling Missing XML Comment Warning
...in VS2010):
Sub PragmaWarningDisableForOpenFile()
DTE.ActiveDocument.Selection.StartOfDocument()
DTE.ActiveDocument.Selection.NewLine()
DTE.ActiveDocument.Selection.LineUp()
DTE.ActiveDocument.Selection.Insert("#pragma warning disable 1591")
DTE.ActiveDocument.Selection.EndOfDo...
Select random lines from a file
...e point is you can keep some lines in memory with shuffle to do the random selection of what to output. Sort is going to sort the entire file, regardless of what your needs are.
– Rubens
Sep 25 '14 at 2:01
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