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CSS styling in Django forms
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Yes and no. First CSS classes are by convention used for styling, if you need an unique identifier its better to use id. Second its usually the template side's responsobilty to do exaclty this, Esspecially if you are going to access this class via frontend me...
How to select rows with no matching entry in another table?
... edited Mar 16 '16 at 12:59
Toby Speight
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answered Nov 2 '10 at 8:56
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How can I generate a unique ID in Python? [duplicate]
...ort later. I'd have to manually kill uuidd as root. I worked around this by setting uuid._uuid_generate_time and uuid._uuid_generate_random to None so the uuid module never used the native implementation. (That should really be an option anyway; generating V4 random UUIDs causing a daemon to be s...
ViewParam vs @ManagedProperty(value = “#{param.id}”)
... if you want the view parameters to survive any validation failures caused by forms enclosed in the view, otherwise you need to manually retain all request parameters for the subsequent requests by <f:param> in the command components.
Example:
<f:metadata>
<f:viewParam id="user_...
Order a MySQL table by two columns
How do I sort a MySQL table by two columns?
5 Answers
5
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How to find duplicates in 2 columns not 1
...e_id,
upcharge_title,
count(*)
from your_table
group by stone_id,
upcharge_title
having count(*) > 1
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Linq to Entities join vs groupjoin
...th child groups. This can be turned into a flat list of parent-child pairs by two small additions:
from p in parents
join c in children on p.Id equals c.Id into g // <= into
from c in g.DefaultIfEmpty() // <= flattens the groups
select new { Parent = p.Value, Child = c?.ChildValu...
How to implement the activity stream in a social network
...t as you can. Structure so that you can quickly grab a batch of activities by activity ID or by using a set of friend IDs with time constraints.
Publish the activity IDs to Redis whenever an activity record is created, adding the ID to an "activity stream" list for every user who is a friend/subscri...
Foreign Key to multiple tables
...pends on your needs.
You could simply create two columns in Ticket, OwnedByUserId and OwnedByGroupId, and have nullable Foreign Keys to each table.
You could create M:M reference tables enabling both ticket:user and ticket:group relationships. Perhaps in future you will want to allow a single tick...
How update the _id of one MongoDB Document?
...rted with a duplicate value in a unique indexed field. You could fix this by doing the delete first, but that is a bad idea because if your insert fails for some reason your data is now lost. You must instead drop your index, perform the work, then restore the index.
– skelly...