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C#: how to get first char of a string?
...
Select the oldest tab to see that it as Matthew
– johnc
Oct 7 '10 at 5:10
11
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How to change the foreign key referential action? (behavior)
...r, so I wrote something to make the statements for me. Figured I'd share:
SELECT
CONCAT('ALTER TABLE `' ,rc.TABLE_NAME,
'` DROP FOREIGN KEY `' ,rc.CONSTRAINT_NAME,'`;')
, CONCAT('ALTER TABLE `' ,rc.TABLE_NAME,
'` ADD CONSTRAINT `' ,rc.CONSTRAINT_NAME ,'` FOREIGN KEY (`',kcu.COLUMN_NAME,
...
How can I reliably determine the type of a variable that is declared using var at design time?
...o resolve the type. For instance:
var items = myList.OfType<Foo>().Select(foo => foo.Bar);
The return type is IEnumerable<Bar>, but resolving this required knowing:
myList is of type that implements IEnumerable.
There is an extension method OfType<T> that applies to IEnume...
What is the difference between single and double quotes in SQL?
...ould be more readable as product_id, so you use either of the following:
SELECT PRODUCT.id AS product_id
SELECT PRODUCT.id 'product_id'
Either works in Oracle, SQL Server, MySQL… but I know some have said that the TOAD IDE seems to give some grief when using the single quotes approach.
You do...
Is there any difference between GROUP BY and DISTINCT
...CT and distinct by UNION cause an oracle error, but GROUP BY worked; I was selecting only 1 column from a view and not using any aggregation; I'm still baffled why it required it, but it does confirm there is some difference in the execution. As others point out, it also lets you GROUP BY columns no...
SQL Server 2008: How to query all databases sizes?
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with fs
as
(
select database_id, type, size * 8.0 / 1024 size
from sys.master_files
)
select
name,
(select sum(size) from fs where type = 0 and fs.database_id = db.database_id) DataFileSizeMB,
(select sum(size) from fs wh...
How to get ID of the last updated row in MySQL?
...)
SET @update_id := 0;
UPDATE some_table SET column_name = 'value', id = (SELECT @update_id := id)
WHERE some_other_column = 'blah' LIMIT 1;
SELECT @update_id;
EDIT by aefxx
This technique can be further expanded to retrieve the ID of every row affected by an update statement:
SET @uids := nul...
How to combine paths in Java?
...oes have a class FilenameUtils that can do this kind of thing, such as the concat() method.
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jQuery OR Selector?
I am wondering if there is a way to have "OR" logic in jQuery selectors. For example, I know an element is either a descendant of an element with class classA or classB, and I want to do something like elem.parents('.classA or .classB') . Does jQuery provide such functionality?
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Convert HashBytes to VarChar
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I have found the solution else where:
SELECT SUBSTRING(master.dbo.fn_varbintohexstr(HashBytes('MD5', 'HelloWorld')), 3, 32)
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