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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...
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 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 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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Primary key/foreign Key naming convention [closed]
...e the USING syntax in SQL to save some typing and some boilerplate noise:
SELECT name, address, amount
FROM employees JOIN payroll USING (employee_id)
Another argument in favor of convention #2 is that it's the way the relational model was designed.
The significance of each column is
part...
How can I restore the MySQL root user’s full privileges?
...Then execute this query:
insert into `user` (`Host`, `User`, `Password`, `Select_priv`, `Insert_priv`, `Update_priv`, `Delete_priv`, `Create_priv`, `Drop_priv`, `Reload_priv`, `Shutdown_priv`, `Process_priv`, `File_priv`, `Grant_priv`, `References_priv`, `Index_priv`, `Alter_priv`, `Show_db_priv`, ...
jQuery AJAX file upload PHP
...t type="file" onchange="saveFile(this)" >
<br><br>
Before selecting the file Open chrome console > network tab to see the request details.
<br><br>
<small>Because in this example we send request to https://stacksnippets.net/upload/image the response code will ...
JavaScript open in a new window, not tab
I have a select box that calls window.open(url) when an item is selected. Firefox will open the page in a new tab by default. However, I would like the page to open in a new window, not a new tab.
...
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...
Efficient paging in SQLite with millions of records
...red field(s), and continue just after them when displaying the next page:
SELECT *
FROM MyTable
WHERE SomeColumn > LastValue
ORDER BY SomeColumn
LIMIT 100;
(This is explained with more detail on the SQLite wiki.)
When you have multiple sort columns (and SQLite 3.15 or later), you can use a ro...