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What is the best place for storing uploaded images, SQL database or disk file system? [closed]
...ll consume a lot of memory. Also, if you use a storage engine that employs table-locks for writes (ISAM for example), your files table might be locked often depending on the size / rate of files you are storing there.
Regarding security - I usually store the files in a directory that is outside of...
How does grep run so fast?
...looks first
for the final letter of the target string, and uses a lookup table to
tell it how far ahead it can skip in the input whenever it finds a
non-matching character.
GNU grep also unrolls the inner loop of Boyer-Moore, and sets up the
Boyer-Moore delta table entries in such a way...
Order discrete x scale by frequency/value
...
ggplot(mtcars, aes(factor(cyl))) + geom_bar()
# Manual levels
cyl_table <- table(mtcars$cyl)
cyl_levels <- names(cyl_table)[order(cyl_table)]
mtcars$cyl2 <- factor(mtcars$cyl, levels = cyl_levels)
# Just to be clear, the above line is no different than:
# mtcars$cyl2 <- factor(m...
The cast to value type 'Int32' failed because the materialized value is null
...eady value. I think, that the error above is occured because CreditHistory table is empty. I have one record in User table and 0 records in CreditHistory table and error is occured. When I use DefaultIfEmpty(0).Sum() it works fine, but with ?? 0 it throws error. My another question is what is best...
SQL Server Restore Error - Access is Denied
I created a database on my local machine and then did a backup called tables.bak of table DataLabTables .
19 Answers
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Selecting data frame rows based on partial string match in a column
...rent approach. I don't know if that's a reference to the %like% from "data.table", but if it is, you can definitely use it as follows.
Note that the object does not have to be a data.table (but also remember that subsetting approaches for data.frames and data.tables are not identical):
library(dat...
TSQL - Cast string to integer or return default value
...> 2147483647 RETURN NULL
RETURN @I
END
GO
-- Testing
DECLARE @Test TABLE(Value nvarchar(50)) -- Result
INSERT INTO @Test SELECT '1234' -- 1234
INSERT INTO @Test SELECT '1,234' -- 1234
INSERT INTO @Test SELECT '1234.0' -- 1234
INSERT INTO @Test SELECT '-1234' ...
Extract a dplyr tbl column as a vector
...yr tbl as a vector, from a tbl with database back-end (i.e. the data frame/table can't be subset directly)?
7 Answers
...
How can I reorder my divs using only CSS?
...ution uses only CSS and works with variable content
#wrapper { display: table; }
#firstDiv { display: table-footer-group; }
#secondDiv { display: table-header-group; }
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improve this answ...
Output array to CSV in Ruby
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I pulled in a CSV file using CSV.table, did some manipulations, got rid of some columns, and now I want to spool the resulting Array of Hashes out again as CSV (really tab-delimited). How to? gist.github.com/4647196
– tamouse
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