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What does the unary plus operator do?
... answered Oct 11 '10 at 2:07
Charles SalviaCharles Salvia
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Common MySQL fields and their appropriate data types
... that is either an ID or references another ID
DATETIME for time stamps
VARCHAR(255) for anything guaranteed to be under 255 characters (page titles, names, etc)
TEXT for pretty much everything else.
Of course there are exceptions, but I find that covers most eventualities.
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In Python, when to use a Dictionary, List or Set?
...om a sequence, and computing mathematical operations such as intersection, union, difference, and symmetric difference.
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How to convert Java String into byte[]?
...u have asked is:
byte[] b = string.getBytes();
byte[] b = string.getBytes(Charset.forName("UTF-8"));
byte[] b = string.getBytes(StandardCharsets.UTF_8); // Java 7+ only
However the problem you appear to be wrestling with is that this doesn't display very well. Calling toString() will just give ...
Why do we always prefer using parameters in SQL statements?
I am very new to working with databases. Now I can write SELECT , UPDATE , DELETE , and INSERT commands. But I have seen many forums where we prefer to write:
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\d is less efficient than [0-9]
...id it was probably more efficient to use a range or digit specifier than a character set.
5 Answers
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INSERT INTO…SELECT for all MySQL columns
... manual. Try this:
INSERT INTO this_table_archive (col1, col2, ..., coln)
SELECT col1, col2, ..., coln
FROM this_table
WHERE entry_date < '2011-01-01 00:00:00';
If the id columns is an auto-increment column and you already have some data in both tables then in some cases you may want to omit t...
Using sed and grep/egrep to search and replace
I am using egrep -R followed by a regular expression containing about 10 unions, so like:
.jpg | .png | .gif etc. This works well, now I would like to replace all strings found with .bmp
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In Java, how do I convert a byte array to a string of hex digits while keeping leading zeros? [dupli
...ffffff" because of sign extension. So one might need to take the last two characters of the returned string.
– Marvo
Jul 27 '12 at 20:55
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How do I use prepared statements in SQlite in Android?
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@jasonhudgins Why not just replace your SELECT with an INSERT? I just came from this thread, where you've confused a beginner
– keyser
May 3 '14 at 15:29
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