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Add a reference column migration in Rails 4
A user has many uploads. I want to add a column to the uploads table that references the user . What should the migration look like?
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Pandas count(distinct) equivalent
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I believe this is what you want:
table.groupby('YEARMONTH').CLIENTCODE.nunique()
Example:
In [2]: table
Out[2]:
CLIENTCODE YEARMONTH
0 1 201301
1 1 201301
2 2 201301
3 1 201302
4 2 ...
MySQL - How to select data by string length
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select * from table order by length(column);
Documentation on the length() function, as well as all the other string functions, is available here.
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Good Hash Function for Strings
...le check - The hashCode() return value will be used by Java to map to some table index before storing the object. So, if the hashCode() returns m, it does something like (m mod k) to get an index of the table of size k. Is that right?
– whitehat
Oct 17 '15 at 2...
The entity type is not part of the model for the current context
...g(DbModelBuilder modelBuilder)
{
modelBuilder.Entity<Estate>().ToTable("Estate");
}
If your tables are not created on startup, this is why. You need to tell the DbContext about them in the OnModelCreating method override.
You can either do custom per-entity mappings here, or separate t...
SQLite - replace part of a string
Is it possible using SQL in an SQLite table to replace part of a string?
3 Answers
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onchange event on input type=range is not triggering in firefox while dragging
...ast either end of the slider
final mouse-up (or touch-end)
The following table shows how at least three different desktop browsers differ in their behaviour with respect to which of the above scenarios they respond to:
Solution:
The onRangeChange function provides a consistent and predictable ...
Web scraping with Python [closed]
...utifulSoup(urllib2.urlopen('http://example.com').read())
for row in soup('table', {'class': 'spad'})[0].tbody('tr'):
tds = row('td')
print tds[0].string, tds[1].string
# will print date and sunrise
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What is the syntax for an inner join in LINQ to SQL?
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It goes something like:
from t1 in db.Table1
join t2 in db.Table2 on t1.field equals t2.field
select new { t1.field2, t2.field3}
It would be nice to have sensible names and fields for your tables for a better example. :)
Update
I think for your query this mig...
jQuery document.createElement equivalent?
...is.$OuterDiv = $('<div></div>')
.hide()
.append($('<table></table>')
.attr({ cellSpacing : 0 })
.addClass("text")
)
;
Update: I thought I'd update this post since it still gets quite a bit of traffic. In the comments below there's some discussi...