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How to avoid the “divide by zero” error in SQL?
...rder to avoid a "Division by zero" error we have programmed it like this:
Select Case when divisor=0 then null
Else dividend / divisor
End ,,,
But here is a much nicer way of doing it:
Select dividend / NULLIF(divisor, 0) ...
Now the only problem is to remember the NullIf bit, if I use the "/"...
Select tableview row programmatically
How do I programmatically select a UITableView row so that
7 Answers
7
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How can I convert tabs to spaces in every file of a directory?
...s on each line;
-t 4 means that each tab will be converted to 4 whitespace chars (8 by default).
sponge is from the moreutils package, and avoids clearing the input file.
Finally, you can use gexpand on OSX, after installing coreutils with Homebrew (brew install coreutils).
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Adding HTML entities using CSS content
... edited Apr 23 '18 at 5:15
Charlie
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answered Oct 10 '08 at 7:27
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MySQL - Rows to Columns
...ms that I'll use for the rest of this post. This will be the base table:
select * from history;
+--------+----------+-----------+
| hostid | itemname | itemvalue |
+--------+----------+-----------+
| 1 | A | 10 |
| 1 | B | 3 |
| 2 | A | 9...
How can I remove or replace SVG content?
...
Here is the solution:
d3.select("svg").remove();
This is a remove function provided by D3.js.
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How to remove unused C/C++ symbols with GCC and ld?
...shorter names for symbols (can help a bit, likely not too much); use const char x[] where possible; ... this paper, though it talks about dynamic shared objects, can contain suggestions that, if followed, can help to make your final binary output size smaller (if your target is ELF).
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How do I pass command line arguments to a Node.js program?
...ecause options that start with a single dash are only supposed to a single character. Anything that follows a single char option is taken as an argument for the option (no space required). Starting the option with two dashes (i.e. --n5) should produce 'n5: true'. This is fairly standard behaviour fo...
Get bitcoin historical data [closed]
I want to do my own bitcoin chart.
7 Answers
7
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Copy data into another table
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If both tables are truly the same schema:
INSERT INTO newTable
SELECT * FROM oldTable
Otherwise, you'll have to specify the column names (the column list for newTable is optional if you are specifying a value for all columns and selecting columns in the same order as newTable's schema)...