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How to make certain text not selectable with CSS [duplicate]
...r my page has some centered text, but I do not want the user to be able to select it. Is there a way to do this with CSS?
2...
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 ...
Is there any difference between GROUP BY and DISTINCT
...CT and distinct by UNION cause an oracle error, but GROUP BY worked; I was selecting only 1 column from a view and not using any aggregation; I'm still baffled why it required it, but it does confirm there is some difference in the execution. As others point out, it also lets you GROUP BY columns no...
How to select first and last TD in a row?
How can you select the first and the last TD in a row?
5 Answers
5
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Copy data into another table
...
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)...
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...
XPath to select multiple tags
...l-name()='e']
is both too-long and incorrect. This XPath expression will select nodes like:
OhMy:c
NotWanted:d
QuiteDifferent:e
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Correct way to use StringBuilder in SQL
...:
StringBuilder sb = new StringBuilder(some_appropriate_size);
sb.append("select id1, ");
sb.append(id2);
sb.append(" from ");
sb.append(table);
return sb.toString();
Note that I've listed some_appropriate_size in the StringBuilder constructor, so that it starts out with enough capacity for the f...
How to increase font size in the Xcode editor?
...)
Go to XCode > Preferences > Fonts & Color
From the 'Theme' box select the theme you want to modify (or select the theme you want to modify and click the "+" button at the bottom of the theme list to clone it first for backup, for there is no undo option)
In the source editor box there is...
PostgreSQL - fetch the row which has the Max value for a column
...sted index lookup into lives - on my machine
-- the latter query plan was selected given my memory settings and
-- histogram
SELECT
l1.*
FROM
lives AS l1
INNER JOIN (
SELECT
usr_id,
MAX(time_stamp) AS time_stamp_max
FROM
lives
GROUP BY
usr_id
) AS l2
...