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python pandas remove duplicate columns
...,False,True].
Pandas allows one to index using boolean values whereby it selects only the True values. Since we want to keep the unduplicated columns, we need the above boolean array to be flipped (ie [True, True, False] = ~[False,False,True])
Finally, df.loc[:,[True,True,False]] selects only the...
Repair all tables in one go
...ing query to print REPAIR SQL statments for all tables inside a database:
select concat('REPAIR TABLE ', table_name, ';') from information_schema.tables
where table_schema='mydatabase';
After that copy all the queries and execute it on mydatabase.
Note: replace mydatabase with desired DB name
...
Surrogate vs. natural/business keys [closed]
...ot more tables into your query than should really be necessary. Compare:
select sum(t.hours)
from timesheets t
where t.dept_code = 'HR'
and t.status = 'VALID'
and t.project_code = 'MYPROJECT'
and t.task = 'BUILD';
against:
select sum(t.hours)
from timesheets t
join departents d on d.dept_i...
jQuery vs document.querySelectorAll
...er , as far as I know, you can achieve the same result with document.querySelector or document.querySelectorAll , which are supported in Internet Explorer 8 and above.
...
How to move columns in a MySQL table?
...min provides a GUI for this within the structure view of a table.
Check to select the column you want to move and click the change action at the bottom of the column list.
You can then change all of the column properties and you'll find the 'move column' function at the far right of the screen.
Of ...
How to ignore files/directories in TFS for avoiding them to go to central source repository?
...ol Explorer. This launches a small wizard, and on one of the steps you can select items to exclude (although, I think you have to add at least one item to TFS with this method for the wizard to let you continue).
You can even add a forbidden patterns check-in policy (under Team -> Team Project S...
How to reset Android Studio
...e list of recent projects. Now right click the item you want to remove and select Remove from list (repeat for all items to remove).
– free3dom
Nov 19 '14 at 7:24
...
How to clear all s’ contents inside a parent ?
...t was asked for in the original question -- you should use a more specific selector.
– Drew Noakes
Aug 10 '11 at 10:48
4
...
Convert data.frame column to a vector?
... The reminder of drop=FALSE is useful - this helps me in cases where I may select N columns from a data.frame, in those cases where N=1.
– Iterator
Aug 15 '11 at 20:42
...
Does the order of LINQ functions matter?
... order by ((record.Score1 + record.Score2) / 2) descending
select new
{
Name = record.Name,
Average = ((record.Score1 + record.Score2) / 2)
};
If, for whatever reason, you decided to "optimize" the ...