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What is base 64 encoding used for?
...You never know -- some protocols may interpret your binary data as control characters (like a modem), or your binary data could be screwed up because the underlying protocol might think that you've entered a special character combination (like how FTP translates line endings).
So to get around th...
INNER JOIN ON vs WHERE clause
...ed is a cartesian product of the tables to which a filter is applied which selects only those rows with joining columns matching.
It's easier to see this with the WHERE syntax.
As for your example, in MySQL (and in SQL generally) these two queries are synonyms.
Also note that MySQL also has a STR...
iPhone Simulator - Simulate a slow connection?
...re” to install it.
There we go!
Be sure to turn it on. You need to select a profile and enable the network conditioner with the big toggle that should be familiar from the Time Machine prefpane.
Caveat
This won't affect localhost, so be sure to use a staging server or co-worker's comput...
psql - save results of command to a file
...peruser privileges and will write to a file on the server.
Example: COPY (SELECT foo, bar FROM baz) TO '/tmp/query.csv' (format csv, delimiter ';')
Creates a CSV file with ';' as the field separator.
As always, see the documentation for details
...
#1071 - Specified key was too long; max key length is 767 bytes
...o 3072 bytes.
You also have to be aware that if you set an index on a big char or varchar field which is utf8mb4 encoded, you have to divide the max index prefix length of 767 bytes (or 3072 bytes) by 4 resulting in 191. This is because the maximum length of a utf8mb4 character is four bytes. For a...
How to execute raw SQL in Flask-SQLAlchemy app
...xecute("<sql here>")
or:
from sqlalchemy import text
sql = text('select name from penguins')
result = db.engine.execute(sql)
names = [row[0] for row in result]
print names
share
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improve...
What is Full Text Search vs LIKE
... can enable support for leading wildcards by pre-compiling suffix trees in selected fields.
Other features typical of full-text search are
lexical analysis or tokenization—breaking a
block of unstructured text into
individual words, phrases, and
special tokens
morphological
analysis, or stemmi...
How can I get around MySQL Errcode 13 with SELECT INTO OUTFILE?
I am trying to dump the contents of a table to a csv file using a MySQL SELECT INTO OUTFILE statement. If I do:
13 Answers...
How to clear a chart from a canvas so that hover events cannot be triggered?
...lt;canvas id="results-graph"><canvas>');
canvas = document.querySelector('#results-graph');
ctx = canvas.getContext('2d');
ctx.canvas.width = $('#graph').width(); // resize to parent width
ctx.canvas.height = $('#graph').height(); // resize to parent height
var x = canvas.width/2;...
How to deselect a selected UITableView cell?
I am working on a project on which I have to preselect a particular cell.
24 Answers
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