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Sorting rows in a data table
We have two columns in a DataTable , like so:
12 Answers
12
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Is there a better way to dynamically build an SQL WHERE clause than by using 1=1 at its beginning?
... offer you:
using (var dbContext = new MyDbContext())
{
IQueryable<Table1Item> query = dbContext.Table1;
if (condition1)
{
query = query.Where(c => c.Col1 == 0);
}
if (condition2)
{
query = query.Where(c => c.Col2 == 1);
}
if (condition3)...
schema builder laravel migrations unique on two columns
...array as the first param to create a unique key across multiple columns.
$table->unique(array('mytext', 'user_id'));
or (a little neater)
$table->unique(['mytext', 'user_id']);
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im...
Facebook database design?
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Keep a friend table that holds the UserID and then the UserID of the friend (we will call it FriendID). Both columns would be foreign keys back to the Users table.
Somewhat useful example:
Table Name: User
Columns:
UserID PK
Emai...
Rails :include vs. :joins
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.joins will just joins the tables and brings selected fields in return. if you call associations on joins query result, it will fire database queries again
:includes will eager load the included associations and add them in memory. :includes loads all...
Angular.js ng-repeat across multiple tr's
...test through an html validator allowed multiple tbody elements in the same table.
Update: As of at least Angular 1.2 there is an ng-repeat-start and ng-repeat-end to allow repeating a series of elements. See the documentation for more information and thanks to @Onite for the comment!
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How are Python's Built In Dictionaries Implemented?
...r python is implemented? My understanding is that it is some sort of hash table, but I haven't been able to find any sort of definitive answer.
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float:left; vs display:inline; vs display:inline-block; vs display:table-cell;
...(the best is simply to not have any spaces between the elements)
display:table-cell;
Another one where you'll have problems with browser compatibility. Older IEs won't work with this at all. But even for other browsers, it's worth noting that table-cell is designed to be used in a context of being...
Repeat each row of data.frame the number of times specified in a column
...ndRows(df, "freq")
Simple syntax, very fast, works on data.frame or data.table.
Result:
var1 var2
1 a d
2 b e
2.1 b e
3 c f
3.1 c f
3.2 c f
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How do I use ROW_NUMBER()?
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For the first question, why not just use?
SELECT COUNT(*) FROM myTable
to get the count.
And for the second question, the primary key of the row is what should be used to identify a particular row. Don't try and use the row number for that.
If you returned Row_Number() in your main...