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MySQL remove all whitespaces from the entire column
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To replace all spaces :
UPDATE `table` SET `col_name` = REPLACE(`col_name`, ' ', '')
To remove all tabs characters :
UPDATE `table` SET `col_name` = REPLACE(`col_name`, '\t', '' )
To remove all new line characters :
UPDATE `table` SET `col_name` = REP...
Counting the number of elements with the values of x in a vector
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You can just use table():
> a <- table(numbers)
> a
numbers
4 5 23 34 43 54 56 65 67 324 435 453 456 567 657
2 1 2 2 1 1 2 1 2 1 3 1 1 1 1
Then you can subset it:
> a[names(a)==435]
4...
T-SQL query to show table definition?
...l show me the full definition, including indexes and keys for a SQL Server table? I want a pure query - and know that SQL Studio can give this to me, but I am often on "wild" computers that have only the most bare-bones apps and I have no rights to install studio. But SQLCMD is always an option.
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float:left; vs display:inline; vs display:inline-block; vs display:table-cell;
...(the best is simply to not have any spaces between the elements)
display:table-cell;
Another one where you'll have problems with browser compatibility. Older IEs won't work with this at all. But even for other browsers, it's worth noting that table-cell is designed to be used in a context of being...
What's the difference between INNER JOIN, LEFT JOIN, RIGHT JOIN and FULL JOIN? [duplicate]
... don't do it for me. Why is the top right picture not simply SELECT * FROM TableA;? Why is the top left picture not simply SELECT * FROM TableB;? Why is the top middle picture not SELECT * FROM A INTERSECT SELECT * FROM B ? etc
– onedaywhen
Sep 9 '11 at 10:41
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Dropping Unique constraint from MySQL table
How can I drop the "Unique Key Constraint" on a column of a MySQL table using phpMyAdmin?
10 Answers
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How to write log base(2) in c/c++
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If you want to make it fast, you could use a lookup table like in Bit Twiddling Hacks (integer log2 only).
uint32_t v; // find the log base 2 of 32-bit v
int r; // result goes here
static const int MultiplyDeBruijnBitPosition[32] =
{
0, 9, 1, 10, 13, 21, 2, 29, 11, 1...
CHECK constraint in MySQL is not working
First I created a table like
8 Answers
8
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How do I escape a reserved word in Oracle?
In TSQL I could use something like Select [table] from tablename to select a column named "table".
5 Answers
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How do you join on the same table, twice, in mysql?
I have 2 tables. One (domains) has domain ids, and domain names (dom_id, dom_url).
3 Answers
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