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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...
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...
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...
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...
How do I create test and train samples from one dataframe with pandas?
...
scikit learn's train_test_split is a good one.
from sklearn.model_selection import train_test_split
train, test = train_test_split(df, test_size=0.2)
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...
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...
How to output MySQL query results in CSV format?
...ech-recipes.com/rx/1475/save-mysql-query-results-into-a-text-or-csv-file/
SELECT order_id,product_name,qty
FROM orders
WHERE foo = 'bar'
INTO OUTFILE '/var/lib/mysql-files/orders.csv'
FIELDS TERMINATED BY ','
ENCLOSED BY '"'
LINES TERMINATED BY '\n';
Using this command columns names will not be e...
Code snippet or shortcut to create a constructor in Visual Studio
...a C# project.
So how to make a constructor
Press Ctrl+K and then Ctrl+X
Select Visual C#
Select ctor
Press Tab
Update: You can also right-click in your code where you want the snippet, and select Insert Snippet from the right-click menu
...
Edit changeset comment after updates have been checked in to TFS
...u know a specific file that was included in the changeset then find it and select it (can be done from the Solution Explorer panel)
right click, select View History (Source Explorer) or Source Control -> View History (Solution Explorer)
find the specific change you are interested in, then ri...