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MySQL Fire Trigger for both Insert and Update
Is it possible to fire a mysql trigger for both the insert and update events of a table?
3 Answers
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'sudo gem install' or 'gem install' and gem locations
Running ' sudo gem list --local ' and ' gem list --local ' give me differing results. My gem path is set to my home folder and only contains the gems from ' gem list --local '.
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How dangerous is it to compare floating point values?
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First of all, floating point values are not "random" in their behavior. Exact comparison can and does make sense in plenty of real-world usages. But if you're going to use floating point you need to be aware of how it works. Erring on the side of assuming floating point ...
Storing JSON in database vs. having a new column for each key
...ing user related data in my table - I have 2 columns - uid (primary key) and a meta column which stores other data about the user in JSON format.
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How can I truncate a datetime in SQL Server?
...at's the best way to truncate a datetime value (as to remove hours minutes and seconds) in SQL Server 2008?
13 Answers
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Fastest way to count exact number of rows in a very large table?
...ECT COUNT(*) FROM TABLE_NAME will be slow when the table has lots of rows and lots of columns.
25 Answers
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How to assign from a function which returns more than one value?
...ge. It does not require a special operator but does require that the left hand side be written using list[...] like this:
library(gsubfn) # need 0.7-0 or later
list[a, b] <- functionReturningTwoValues()
If you only need the first or second component these all work too:
list[a] <- function...
How to design a database for User Defined Fields?
...s a variant of #2). This answer is specifically tailored to this situation and the description of the data distribution and access patterns described.
Pros:
Because you indicate that some UDFs
have values for a small portion of
the overall data set, a separate
table would give you the best
perfor...
What does tree-ish mean in Git?
...ately leads to a (sub)directory
tree (Git refers to directories as "trees" and "tree objects").
In the original poster's case, foo is a directory that he wants to
specify. The correct way to specify a (sub)directory in Git is to use this
"tree-ish" syntax (item #15 from the Git revisions documentat...
What are the differences between the BLOB and TEXT datatypes in MySQL?
What is blob and what is text ? What are the differences?
6 Answers
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