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How to select date from datetime column?
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The first one is very slow and ignores the indexes. It is better to have LIKE 'date%'
– kachar
Feb 22 '13 at 10:03
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How to grep for two words existing on the same line? [duplicate]
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grep "word1" FILE will print all lines that have word1 in them from FILE, and then grep "word2" will print the lines that have word2 in them. Hence, if you combine these using a pipe, it will show lines containing both word1 and word2.
If you just want a count of how many lines had the 2 words on ...
Is there still any reason to learn AWK?
...you move to more exotic systems, knowing a little awk is going to be Real Handy.
awk can also be used for more than just text processing. For example one of my supervisors writes astronomy code in awk - that is how utterly old school and awesome he is. Back in his days, it was the best tool for the...
How to design a product table for many kinds of product where each product has many parameters
...stead, one table per product type, storing both common product attributes, and product-specific attributes.
Serialized LOB: One table for Products, storing attributes common to all product types. One extra column stores a BLOB of semi-structured data, in XML, YAML, JSON, or some other format. This...
How are the points in CSS specificity calculated
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Pekka's answer is practically correct, and probably the best way to think about the issue.
However, as many have already pointed out, the W3C CSS recommendation states that "Concatenating the three numbers a-b-c (in a number system with a large base) gives the sp...
Comparing HTTP and FTP for transferring files
...TP used to be generally considered faster. FTP requires a control channel and state be maintained besides the TCP state but HTTP does not. There are 6 packet transfers before data starts transferring in FTP but only 4 in HTTP.
I think a properly tuned TCP layer would have more effect on speed tha...
How to commit my current changes to a different branch in Git [duplicate]
Sometimes it happens that I make some changes in my working directory, and I realize that these changes should be committed in a branch different to the current one. This usually happens when I want to try out new things or do some testing and I forget to create a new branch beforehand, but I don't ...
Get to UIViewController from UIView?
...r directly.
The view should instead be independent of the view controller, and be able to work in different contexts.
Should you need the view to interface in a way with the view controller, the recommended way, and what Apple does across Cocoa is to use the delegate pattern.
An example of how to ...
Dealing with multiple Python versions and PIP?
...This is the recommendation because it works across all versions of Python, and in all forms of virtualenv. For example:
# The system default python:
$ python -m pip install fish
# A virtualenv's python:
$ .env/bin/python -m pip install fish
# A specific version of python:
$ python-3.6 -m pip inst...
Javascript object Vs JSON
I want to understand the basic differences clearly between Javascript object and JSON string.
5 Answers
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