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How can you determine how much disk space a particular MySQL table is taking up?
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For a table mydb.mytable run this for:
BYTES
SELECT (data_length+index_length) tablesize
FROM information_schema.tables
WHERE table_schema='mydb' and table_name='mytable';
KILOBYTES
SELECT (data_length+index_length)/power(1024,1) tablesize_kb
FROM information_schema....
Get list of databases from SQL Server
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Execute:
SELECT name FROM master.sys.databases
This the preferred approach now, rather than dbo.sysdatabases, which has been deprecated for some time.
Execute this query:
SELECT name FROM master.dbo.sysdatabases
or if you pref...
In STL maps, is it better to use map::insert than []?
...<std::endl;
}
};
int Sample::_noOfObjects = 0;
int main(int argc, char* argv[])
{
Sample sample;
std::map<int,Sample> map;
map.insert( std::make_pair<int,Sample>( 1, sample) );
//map[1] = sample;
return 0;
}
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How can I remove or replace SVG content?
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Here is the solution:
d3.select("svg").remove();
This is a remove function provided by D3.js.
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Simplest way to read json from a URL in java
...tStreamReader;
import java.io.Reader;
import java.net.URL;
import java.nio.charset.Charset;
import org.json.JSONException;
import org.json.JSONObject;
public class JsonReader {
private static String readAll(Reader rd) throws IOException {
StringBuilder sb = new StringBuilder();
int cp;
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How to select date without time in SQL
When I select date in SQL it is returned as 2011-02-25 21:17:33.933 . But I need only the Date part, that is 2011-02-25 . How can I do this?
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minimum double value in C/C++
...tion just has to work around it. See the floating-point model in 5.2.4.2.2 Characteristics of floating types <float.h> p2 of C99 (may have been moved elsewhere since then).
– user743382
Nov 10 '14 at 22:23
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How to drop columns by name in a data frame
..."z","u"))]
x y
1 1 2
2 2 3
3 3 4
4 4 5
5 5 6
Or, much simpler, use the select argument of the subset function : you can then use the - operator directly on a vector of column names, and you can even omit the quotes around the names !
R> subset(df, select=-c(z,u))
x y
1 1 2
2 2 3
3 3 4
4 4 ...
Cherry pick using TortoiseGit
...y with the target branch checked out.
Use the top-left blue branch name to select the source branch.
Select the commit(s) you want.
Right click and select Cherry Pick this commit.
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MySQL: Selecting multiple fields into multiple variables in a stored procedure
Can I SELECT multiple columns into multiple variables within the same select query in MySQL?
3 Answers
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