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Getting “Lock wait timeout exceeded; try restarting transaction” even though I'm not using a transac
...heck your database transaction isolation level in the mysql cli:
mysql> SELECT @@GLOBAL.tx_isolation, @@tx_isolation, @@session.tx_isolation;
+-----------------------+-----------------+------------------------+
| @@GLOBAL.tx_isolation | @@tx_isolation | @@session.tx_isolation |
+----------------...
Apply multiple functions to multiple groupby columns
... group. When aggregating, g will be a Series. Passing g.index to df.ix[] selects the current group from df. I then test if column C is less than 0.5. The returned boolean series is passed to g[] which selects only those rows meeting the criteria.
In [95]: cust = lambda g: g[df.loc[g.index]['C']...
what is reverse() in Django
... question = get_object_or_404(Question, pk=question_id)
try:
selected = question.choice_set.get(pk=request.POST['choice'])
except KeyError:
# handle exception
pass
else:
selected.votes += 1
selected.save()
return HttpResponseRedirect(reve...
Sleep Command in T-SQL?
...(@hours * 60) * 60)) - (@mins * 60)
IF @hours > 23
BEGIN
select @hours = 23
select @mins = 59
select @secs = 59
-- 'maximum wait time is 23 hours, 59 minutes and 59 seconds.'
END
declare @sql nvarchar(24) = 'WAITFOR DELAY '+char(39)+cast(@hours as nvarchar(2))...
How to determine whether code is running in DEBUG / RELEASE build?
...processor Macros' for debug to ensure that DEBUG is being set - do this by selecting the project and clicking on the build settings tab. Search for DEBUG and look to see if indeed DEBUG is being set.
Pay attention though. You may see DEBUG changed to another variable name such as DEBUG_MODE.
th...
Are database triggers evil? [closed]
...lumns wouldn't exist and you'd have to process a function on each row when selecting them. That's likely to kill DBMS performance, far better to create the auto-generated column at insert/update time since that's the only time it changes.
Also, lack of triggers would prevent data rules from being e...
Will #if RELEASE work like #if DEBUG does in C#?
...nstant defined for release mode. Check your project settings under build.
Selecting [Define DEBUG constant] under Project -> Build is like including #define DEBUG at the beginning of every file.
If you want to define a RELEASE constant for the release configuration go to:
Project Properties ...
mongodb: insert if not exists
...what data you want to write:
data = {"$set":{"key2":"value2"}}
Now your selected document will update the value of "key2" only and leave everything else untouched.
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How do I update a Linq to SQL dbml file?
... was getting 'Specified cast is not valid' errors when performing a simple select on a view. Including 1b fixed it for me
– tomfumb
Nov 29 '11 at 19:40
6
...
jQuery: fire click() before blur() event
...opdown from stealing focus. The slight advantage is that the value will be selected when the mouse button is released, which is how native select components work. JSFiddle
$('input').on('focus', function() {
$('ul').show();
}).on('blur', function() {
$('ul').hide();
});
$('ul').on('mousedo...