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How to delete from select in MySQL?
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SELECT (sub)queries return result sets. So you need to use IN, not = in your WHERE clause.
Additionally, as shown in this answer you cannot modify the same table from a subquery within the same query. However, you can either...
How do I change tab size in Vim?
...hat's what would happen should tabs be used, rather than always delete one char at a time).
To make a fully educated decision as to how to set things up, you'll need to read Vim docs on tabstop, shiftwidth, softtabstop and expandtab. The most interesting bit is found under expandtab (:help 'expandta...
Difference between natural join and inner join
...+----------+
The INNER JOIN of TableA and TableB on Column1 will return
SELECT * FROM TableA AS a INNER JOIN TableB AS b USING (Column1);
SELECT * FROM TableA AS a INNER JOIN TableB AS b ON a.Column1 = b.Column1;
+------------+-----------+---------------------+
| a.Column1 | a.Column2 | ...
INSERT INTO…SELECT for all MySQL columns
... manual. Try this:
INSERT INTO this_table_archive (col1, col2, ..., coln)
SELECT col1, col2, ..., coln
FROM this_table
WHERE entry_date < '2011-01-01 00:00:00';
If the id columns is an auto-increment column and you already have some data in both tables then in some cases you may want to omit t...
Retrieving the text of the selected in element
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function getSelectedText(elementId) {
var elt = document.getElementById(elementId);
if (elt.selectedIndex == -1)
return null;
return elt.options[elt.selectedIndex].text;
}
var text = getSelectedText('test');
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Query to count the number of tables I have in MySQL
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SELECT COUNT(*) FROM information_schema.tables WHERE table_schema = 'dbName';
Source
This is mine:
USE databasename;
SHOW TABLES;
SELECT FOUND_ROWS();
...
Select tableview row programmatically
How do I programmatically select a UITableView row so that
7 Answers
7
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How can I return two values from a function in Python?
...s, but you can return a tuple or a list and unpack it after the call:
def select_choice():
...
return i, card # or [i, card]
my_i, my_card = select_choice()
On line return i, card i, card means creating a tuple. You can also use parenthesis like return (i, card), but tuples are created ...
Check if table exists in SQL Server
...nge from version to version.
To check if a table exists use:
IF (EXISTS (SELECT *
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_SCHEMA = 'TheSchema'
AND TABLE_NAME = 'TheTable'))
BEGIN
--Do Stuff
END
...
How to find elements by class
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CSS selectors
single class first match
soup.select_one('.stylelistrow')
list of matches
soup.select('.stylelistrow')
compound class (i.e. AND another class)
soup.select_one('.stylelistrow.otherclassname')
soup.select('.st...