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add column to mysql table if it does not exist
... for 1060 begin end;
alter table atable add subscriber_surname varchar(64);
end;;
call foo();;
I think its neater this way than with an exists subquery. Especially if you have a lot of columns to add, and you want to run the script several times.
more info on continue handlers can be found at...
How to change the Eclipse default workspace?
... erakitin
10.3k55 gold badges3939 silver badges4646 bronze badges
answered Mar 3 '11 at 10:24
Manrico CorazziManrico Corazzi
1...
How can I check if a Perl array contains a particular value?
....73/s (n=100000)
first: 1 wallclock secs ( 0.63 usr + 0.01 sys = 0.64 CPU) @ 156250.00/s (n=100000)
grep: 42 wallclock secs (41.95 usr + 0.08 sys = 42.03 CPU) @ 2379.25/s (n=100000)
hash: 0 wallclock secs ( 0.01 usr + 0.00 sys = 0.01 CPU) @ 10000000.00/s (n=100000)
...
Check, using jQuery, if an element is 'display:none' or block on click
...ble")
and
$("#selector").is(":hidden")
You can also execute commands based on visibility in the selector;
$("#selector:visible").hide()
or
$("#selector:hidden").show()
share
|
improve th...
Python list of dictionaries search
...a/quQzv (method names see below).
All tests done with Python 3.6.4, W7x64.
from random import randint
from timeit import timeit
list_dicts = []
for _ in range(1000): # number of dicts in the list
dict_tmp = {}
for i in range(10): # number of keys for each dict
dict_tmp[f...
Getting a slice of keys from a map
... not much more work, and in my tests (using a map with 1,000,000 random int64 keys and then generating the array of keys ten times with each method), it was about 20% faster to assign members of the array directly than to use append.
Although setting the capacity eliminates reallocations, append st...
Rotate axis text in python matplotlib
...line 23, in <module> plt.setp(time, rotation=90) File "/usr/lib64/python2.7/site-packages/matplotlib/pyplot.py", line 183, in setp ret = _setp(*args, **kwargs) File "/usr/lib64/python2.7/site-packages/matplotlib/artist.py", line 1199, in setp func = getattr(o, funcName) Attribu...
Converting Long to Date in Java returns 1970
...put of seconds, and multiply by a thousand. Note that the result must be a 64-bit long as we would overflow a 32-bit int.
long input = 1_220_227_200L; // Note the "L" appended to long integer literals.
long milliseconds = ( input * 1_000L ); // Use a "long", not the usual "int". Note the appended "...
How to compute the similarity between two text documents?
... the similarity value between the first document and the third (using zero-based indexing), which is the same value that you find at (2,0), because cosine similarity is commutative.
– Fred Foo
Aug 26 '12 at 11:24
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How can I connect to MySQL in Python 3 on Windows?
...sing ActiveState Python 3 on Windows and wanted to connect to my MySQL database.
I heard that mysqldb was the module to use.
I can't find mysqldb for Python 3.
...