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How to find out the MySQL root password
... did the following:
sudo service mysql stop
sudo mysqld_safe --skip-grant-tables --skip-syslog --skip-networking
Then run mysql in a new terminal:
mysql -u root
And run the following queries to change the password:
UPDATE mysql.user SET authentication_string=PASSWORD('password') WHERE User='r...
Aggregate / summarize multiple variables per group (e.g. sum, mean)
...
Using the data.table package, which is fast (useful for larger datasets)
https://github.com/Rdatatable/data.table/wiki
library(data.table)
df2 <- setDT(df1)[, lapply(.SD, sum), by=.(year, month), .SDcols=c("x1","x2")]
setDF(df2) # con...
Are Stored Procedures more efficient, in general, than inline statements on modern RDBMS's? [duplica
...at is generated is sub-optimal.
For example, if you send SELECT *
FROM table WHERE id BETWEEN 1 AND
99999999, the DBMS may select a
full-table scan instead of an index
scan because you're grabbing every row
in the table (so sayeth the
statistics). If this is the cached
version, then ...
how to generate migration to make references polymorphic
I have a Products table and want to add a column:
4 Answers
4
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Serializing object that contains cyclic object value
... goes.
One feature that's not as well-known as JSON.stringify() is console.table(). Simply call console.table(whatever);, and it will log the variable in the console in tabular format, making it rather quite easy and convenient to peruse the variable's contents.
...
Changing Font Size For UITableView Section Headers
...instruct me on the easiest way to change the font size for the text in a UITableView section header?
11 Answers
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Why the switch statement cannot be applied on strings?
...
Additionally, C/C++ switch statements are typically generated as branch tables. It's not nearly as easy to generate a branch table for a string style switch.
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Adding an onclick function to go to url in JavaScript?
... 2) want to wait until it completely loads 3) so that, that web page has a table from which I need to extract all the rows. I can able to perform step 1 and if I am on already loaded website then in console I am able to extract table rows (in javascript code). But, when I am trying to write code se...
MySQL Orderby a number, Nulls last
...sign (-) before the column name and switch the ASC to DESC:
SELECT * FROM tablename WHERE visible=1 ORDER BY -position DESC, id DESC
It is essentially the inverse of position DESC placing the NULL values last but otherwise the same as position ASC.
A good reference is here http://troels.arvin.dk...
Capturing URL parameters in request.GET
...h/?q=CA. The query part '?q=CA' will be automatically reserved in the hash table which you can reference though
request.GET.get('q', None).
Here is an example (file views.py)
class CityListView(generics.ListAPIView):
serializer_class = CityNameSerializer
def get_queryset(self):
if ...