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Are there any disadvantages to always using nvarchar(MAX)?
..., the value gets pushed out of row based on may more factors, including sp_tableoptions: msdn.microsoft.com/en-us/library/ms173530.aspx. VARCHAR(255) types can also b pushed out of row, the 'overhead' mentioned may be exactly the same for MAX and 255. It compares MAX types with TEXT types, when they...
How do I efficiently iterate over each entry in a Java Map?
...r();
while (it.hasNext()) {
i += it.next() + it.getValue();
}
Using MutableMap of Eclipse (CS) collections
final long[] i = {0};
mutableMap.forEachKeyValue((key, value) -> {
i[0] += key + value;
});
Perfomance tests (mode = AverageTime, system = Windows 8.1 64-bit, Intel i7-4790 3.6...
How to escape a pipe char in a code statement in a markdown table?
On GitHub I want to build a table containing pieces of code in Markdown. It works fine except when I put a pipe char (i.e. | ) between the backtick (i.e. ` ) chars.
...
Using Position Relative/Absolute within a TD?
...
This is because according to CSS 2.1, the effect of position: relative on table elements is undefined. Illustrative of this, position: relative has the desired effect on Chrome 13, but not on Firefox 4. Your solution here is to add a div around your content and put the position: relative on that di...
unresolved reference to object [INFORMATION_SCHEMA].[TABLES]
I've created a UDF that accesses the [INFORMATION_SCHEMA].[TABLES] view:
3 Answers
3...
What are some (concrete) use-cases for metaclasses?
... About the ORM case, are you talking about the class-based way of defining tables, or the metaclasses on mapped objects. Because SQLAlchemy can (rightly) map to any class (and I am assuming that it doesn't use a metaclass for that activity).
– Ali Afshar
Dec 24...
Switch statement fallthrough in C#?
...ere one takes a value, computes an offset from it (whether by looking up a table indexed by a perfect hash of the value, or by actual arithmetic on the value*). It's worth noting at this point that today, C# compilation will sometimes turn switch into the equivalent if-else, and sometimes use a hash...
How to return only the Date from a SQL Server DateTime datatype
...PU time taken to perform all the pieces. If both queries are run against a table with millions of rows, the CPU time using DateDiff can be close to 1/3rd of the Convert CPU time!
To see execution plans for queries:
set showplan_text on
GO
Both DATEADD and DATEDIFF will execute a CONVERT_IMPLICI...
How to count TRUE values in a logical vector
...values.
See for example:
z <- c(TRUE, FALSE, NA)
sum(z) # gives you NA
table(z)["TRUE"] # gives you 1
length(z[z == TRUE]) # f3lix answer, gives you 2 (because NA indexing returns values)
So I think the safest is to use na.rm = TRUE:
sum(z, na.rm = TRUE) # best way to count TRUE values
(whi...
Reset the database (purge all), then seed a database
Is there a rake command to wipe out the data in the database tables?
6 Answers
6
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