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SQL Logic Operator Precedence: And and Or
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296
And has precedence over Or, so, even if a <=> a1 Or a2
Where a And b
is not the same...
Replace specific characters within strings
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With a regular expression and the function gsub():
group <- c("12357e", "12575e", "197e18", "e18947")
group
[1] "12357e" "12575e" "197e18" "e18947"
gsub("e", "", group)
[1] "12357" "12575" "19718" "18947"
What gsub does here is to replace each occurrence of "e" with an empty string ""....
How do I convert from BLOB to TEXT in MySQL?
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266
That's unnecessary. Just use SELECT CONVERT(column USING utf8) FROM..... instead of just SELEC...
Iterating over dictionaries using 'for' loops
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5552
key is just a variable name.
for key in d:
will simply loop over the keys in the dictionary...
Explicitly calling return in a function or not
...turn. The following plot is created from data selected this way:
bench_nor2 <- function(x,repeats) { system.time(rep(
# without explicit return
(function(x) vector(length=x,mode="numeric"))(x)
,repeats)) }
bench_ret2 <- function(x,repeats) { system.time(rep(
# with explicit return
(function(...
What is __future__ in Python used for and how/when to use it, and how it works
...g context managers, you had to do from __future__ import with_statement in 2.5, as the with keyword was new and shouldn't be used as variable names any longer. In order to use with as a Python keyword in Python 2.5 or older, you will need to use the import from above.
Another example is
from __fut...
Swift: Pass array by reference?
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edited Nov 15 '17 at 21:23
iwasrobbed
44.5k2020 gold badges138138 silver badges187187 bronze badges
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Add alternating row color to SQL Server Reporting services report
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213
Go to the table row's BackgroundColor property and choose "Expression..."
Use this expression...
byte[] to hex string [duplicate]
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There is a built in method for this:
byte[] data = { 1, 2, 4, 8, 16, 32 };
string hex = BitConverter.ToString(data);
Result: 01-02-04-08-10-20
If you want it without the dashes, just remove them:
string hex = BitConverter.ToString(data).Replace("-", string.Empty);
Result: 0...