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Select rows of a matrix that meet a condition
...20, ncol = 4)
colnames(m) <- letters[1:4]
The following command will select the first row of the matrix above.
subset(m, m[,4] == 16)
And this will select the last three.
subset(m, m[,4] > 17)
The result will be a matrix in both cases.
If you want to use column names to select columns...
PostgreSQL: insert from another table
...
Just supply literal values in the SELECT:
INSERT INTO TABLE1 (id, col_1, col_2, col_3)
SELECT id, 'data1', 'data2', 'data3'
FROM TABLE2
WHERE col_a = 'something';
A select list can contain any value expression:
But the expressions in the select list do...
How do I kill all the processes in Mysql “show processlist”?
...peration saves time. Do it in MySql itself:
Run these commands
mysql> select concat('KILL ',id,';') from information_schema.processlist
where user='root' and time > 200 into outfile '/tmp/a.txt';
mysql> source /tmp/a.txt;
Reference
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if you do not want to sto...
Changing navigation bar color in Swift
...UIColor.whiteColor()
UINavigationBar.appearance().barTintColor = Style.SELECTED_COLOR
UINavigationBar.appearance().translucent = false
UINavigationBar.appearance().clipsToBounds = false
UINavigationBar.appearance().backgroundColor = Style.SELECTED_COLOR
UINavigationBar.appearance...
How to open a specific port such as 9090 in Google Compute Engine
...hoose "Firewalls rules"
Choose "Create Firewall Rule"
To apply the rule to select VM instances, select Targets > "Specified target tags", and enter into "Target tags" the name of the tag. This tag will be used to apply the new firewall rule onto whichever instance you'd like. Then, make sure the ...
Import .bak file to a database in SQL server
...t only accept a restore from that point? I find it very odd that I can not select a backup file to restore.
– James
Nov 21 '16 at 18:49
13
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How to hide one item in an Android Spinner
...d spinner widget. This would allow you to simulate a spinner with no items selected, and ensures that the onItemSelected() callback is always called for every item selected (if the hidden item is the "current" one). Normally there is always one item in the spinner that doesn't generate a callback, n...
How can I suppress column header output for a single SQL statement?
...in batch (using the mysql command-line binary). I want one of my several SELECT statements to not print the column headers, just the selected records. Is this possible?
...
Select records from NOW() -1 Day
... by >= NOW() -1 so all records from the day before today to the future are selected?
6 Answers
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IntelliJ does not show 'Class' when we right click and select 'New'
... and must have something wrong because when we right click on a directory, select New and then get the context menu, Java based options are not shown. Currently get things like File, some HTML options, XML options.
...