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Best way to test if a row exists in a MySQL table
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Suggest you not to use Count because count always makes extra loads for db use SELECT 1 and it returns 1 if your record right there otherwise it returns null and you can handle it.
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How to reshape data from long to wide format
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And, as of data.table v1.9.6 we can cast on multiple columns
## add an extra column
dat1[, value2 := value * 2]
## cast multiple value columns
dcast(dat1, name ~ numbers, value.var = c("value", "value2"))
# name value_1 value_2 value_3 value_4 value2_1 value2_2 value2_3 ...
Is it valid to have a html form inside another html form?
...d with "form" attribute ("form owner").
As for HTML 4.x you can:
Use an extra form(s) with only hidden fields & JavaScript to set its input's and submit the form.
Use CSS to line up several HTML form to look like a single entity - but I think that's too hard.
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twitter bootstrap navbar fixed top overlapping site
...nder the responsive CSS import, then I still get the body padding, plus an extra line in the menu bar.
– slothbear
May 19 '13 at 3:03
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Python memory leaks [closed]
...bably give you some more hints too. You should also take a look on all the extra helpers provided by pyrasite (such as the memory viewer).
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How to migrate GIT repository from one server to a new one
...ation under that section of the config - and cloning it without taking any extra steps will lose branches other than trunk. It's possible to deal with these problems, but, really - just rsync it.
– bdonlan
Sep 28 '09 at 14:13
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How can I multiply all items in a list together with Python?
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@wordsforthewise probably it's that going through an extra function (lambda) adds overhead, whereas operator.mul goes straight to C.
– whereswalden
Nov 9 '15 at 20:32
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What is the main purpose of setTag() getTag() methods of View?
... Unlike IDs, tags are not used to identify views. Tags are essentially an extra piece of information that can be associated with a view. They are most often used as a convenience to store data related to views in the views themselves rather than by putting them in a separate structure.
Reference:...
How do I query if a database schema exists
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Just to be extra "defensive", the following version generates a Type conversion error to account for the possibility (however unlikely) of > 1 matching Schema's similar to how validation code often intentionally Throw Exception's bec...
How do I calculate the date six months from the current date using the datetime Python module?
...ning for folks wondering if the function is broken because they forgot the extra s in months.
– shad0w_wa1k3r
Jul 30 '19 at 9:19
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