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How to use arguments from previous command?
... see:
$ echo ace
By the way, you could have put the echo on the line by selecting argument 0:
Press Alt-0 Alt-Ctrl-y
Edit:
To answer the question you added to your original:
You can press Alt-0 then repeatedly press Alt-. to step through the previous commands (arg 0). Similarly Alt-- then rep...
What does the “map” method do in Ruby?
...
map, along with select and each is one of Ruby's workhorses in my code.
It allows you to run an operation on each of your array's objects and return them all in the same place. An example would be to increment an array of numbers by one:
[...
Query a parameter (postgresql.conf setting) like “max_connections”
... SHOW, such as minimum
and maximum values.
For your original request:
SELECT *
FROM pg_settings
WHERE name = 'max_connections';
Finally, there is current_setting(), which can be nested in DML statements:
SELECT current_setting('max_connections');
Related:
How to test my ad-hoc SQL wit...
SQL Server database backup restore on lower version
...te a script for all objects and use the script to generate database.
select "Schema and Data" - if you want to Take both the
things in to the Backup script file select Schema Only -
if only schema is needed.
Yes, now you have done with the Create Script with Schema and Data of the...
How to click or tap on a TextView text
...ewIn) {
try {
Log.d(TAG,"GMAIL account selected");
} catch (Exception except) {
Log.e(TAG,"Ooops GMAIL account selection problem "+except.getMessage());
}
}
});
the text view is declared lik...
What is InnoDB and MyISAM in MySQL?
... INSERT statement can be executed to add rows to the end of the table with select at same time if there are no holes/deleted rows in middle of table (at time of concurrent insert).
The default isolation level og mysql InnoDB is "Read Repeatable". For MyISAM, there is no transaction. InnoDB uses row...
Improve INSERT-per-second performance of SQLite
...ple threads (connection per-thread).
First find the items, in the table:
SELECT COUNT(*) FROM table
then read in pages (LIMIT/OFFSET):
SELECT * FROM table ORDER BY _ROWID_ LIMIT <limit> OFFSET <offset>
where and are calculated per-thread, like this:
int limit = (count + n_threa...
How to force GitHub Pages build?
...nstead, if using Chrome, inspect your page, head into the Application tab, select "Clear storage" in the left menu, and click on "Clear site data" at the bottom of the menu.
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How to enter a multi-line command
...e grave accent (backtick):
Get-ChildItem -Recurse `
-Filter *.jpg `
| Select LastWriteTime
However, this is only ever necessary in such cases as shown above. Usually you get automatic line continuation when a command cannot syntactically be complete at that point. This includes starting a new...
How to make a .jar out from an Android Studio project
...enerated jar into your required project's lib folder-->right click-->select "add as library"
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