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How do you connect to multiple MySQL databases on a single webpage?
...d);
$dbh2 = mysql_connect($hostname, $username, $password, true);
mysql_select_db('database1', $dbh1);
mysql_select_db('database2', $dbh2);
Then to query database 1 pass the first link identifier:
mysql_query('select * from tablename', $dbh1);
and for database 2 pass the second:
mysql_query...
Any way to select without causing locking in MySQL?
...s/22-mysql-with-nolock.aspx
in MS SQL Server you would do the following:
SELECT * FROM TABLE_NAME WITH (nolock)
and the MYSQL equivalent is
SET SESSION TRANSACTION ISOLATION LEVEL READ UNCOMMITTED ;
SELECT * FROM TABLE_NAME ;
SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ ;
EDIT
Mic...
Consistency of hashCode() on a Java string
....x the hashCode
function for long Strings worked by
sampling every nth character. This
pretty well guaranteed you would have
many Strings hashing to the same
value, thus slowing down Hashtable
lookup. In JDK 1.2 the function has
been improved to multiply the result
so far by 31 then ...
jQuery or CSS selector to select all IDs that start with some string [duplicate]
How can I select all elements whose id starts with "player_"?
4 Answers
4
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select into in mysql
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Use the CREATE TABLE SELECT syntax.
http://dev.mysql.com/doc/refman/5.0/en/create-table-select.html
CREATE TABLE new_tbl SELECT * FROM orig_tbl;
share
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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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improve this answer
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How to select from subquery using Laravel Query Builder?
... Note that if you have a complex query as a belongsToMany as subselect you have to add getQuery() twice => $sub->getQuery()->getQuery()
– Jordi Puigdellívol
Aug 28 '15 at 14:23
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How to select rows with no matching entry in another table?
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Here's a simple query:
SELECT t1.ID
FROM Table1 t1
LEFT JOIN Table2 t2 ON t1.ID = t2.ID
WHERE t2.ID IS NULL
The key points are:
LEFT JOIN is used; this will return ALL rows from Table1, regardless of whether or not there is a matching row i...
How to detect when cancel is clicked on file input?
...s not exposed to the browser." This is not true if the dialog is closed by selecting a file.
– Trevor
Dec 1 '16 at 22:24
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How does one reorder columns in a data frame?
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You can also use the subset function:
data <- subset(data, select=c(3,2,1))
You should better use the [] operator as in the other answers, but it may be useful to know that you can do a subset and a column reorder operation in a single command.
Update:
You can also use the select...