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Update multiple rows in same query using PostgreSQL
...;
-- populate table with dummy rows
insert into results_dummy
(id, status)
select unnest(array[1,2,3,4,5]::int[]) as id, unnest(array['a','b','c','d','e']::text[]) as status;
select * from results_dummy;
-- THE update of multiple rows with/by different values
update results_dummy as rd
set stat...
Is there a MySQL option/feature to track history of changes to records?
...i AFTER INSERT ON MyDB.data FOR EACH ROW
INSERT INTO MyDB.data_history SELECT 'insert', NULL, NOW(), d.*
FROM MyDB.data AS d WHERE d.primary_key_column = NEW.primary_key_column;
CREATE TRIGGER MyDB.data__au AFTER UPDATE ON MyDB.data FOR EACH ROW
INSERT INTO MyDB.data_history SELECT 'up...
how to schedule a job for sql query to run daily?
...QL Server Agent node and right click the Jobs node in SQL Server Agent and select 'New Job'
In the 'New Job' window enter the name of the job and a description on the 'General' tab.
Select 'Steps' on the left hand side of the window and click 'New' at the bottom.
In the 'Steps' window enter a step n...
Reading a binary file with python
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See this answer if you need to convert an unpacked char[] to a string.
– PeterM
May 20 '16 at 14:57
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Adding additional data to select options using jQuery
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HTML Markup
<select id="select">
<option value="1" data-foo="dogs">this</option>
<option value="2" data-foo="cats">that</option>
<option value="3" data-foo="gerbils">other</option>
</select&...
Rails :include vs. :joins
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.joins will just joins the tables and brings selected fields in return. if you call associations on joins query result, it will fire database queries again
:includes will eager load the included associations and add them in memory. :includes loads all the included tabl...
Computed / calculated / virtual / derived columns in PostgreSQL
...y as column?
The expression (looking like a column) is not included in a SELECT * FROM tbl, though. You always have to list it explicitly.
Can also be supported with a matching expression index - provided the function is IMMUTABLE. Like:
CREATE FUNCTION col(tbl) ... AS ... -- your computed expr...
jquery how to empty input field
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On a related note, .val([]) can also unselect any selected option in select list... not so much with .val(''). Best thing about it is it's cross-browser support. P.S: This is an alternative to only other efficient cross-browser solution - $("select option").prop("...
How to read contacts on Android 2.0
...,
ContactsContract.Contacts.HAS_PHONE_NUMBER,
};
String SELECTION = ContactsContract.Contacts.HAS_PHONE_NUMBER + "='1'";
Cursor contacts = managedQuery(contactUri, PROJECTION, SELECTION, null, null );
The above chunk of code returns a Cursor that points to the resulting query t...
Firefox ignores option selected=“selected”
If you change a dropdown and refresh the page, Firefox seems to ignore the selected attribute.
20 Answers
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