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SQL Call Stored Procedure for each Row without using a cursor
...rate over all customers
WHILE (1 = 1)
BEGIN
-- Get next customerId
SELECT TOP 1 @CustomerID = CustomerID
FROM Sales.Customer
WHERE CustomerID > @CustomerId
ORDER BY CustomerID
-- Exit loop if no more customers
IF @@ROWCOUNT = 0 BREAK;
-- call your sproc
EXEC dbo.YOURSPROC...
Nullable Foreign Key bad practice?
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Using NULL would be a good way to clean up incomplete orders:
SELECT * FROM `orders`
WHERE `started_time` < (UNIX_TIMESTAMP() + 900) AND `customer_id` IS NULL
The above would show orders older than 15 minutes without a related customer ID.
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How do MySQL indexes work?
...be faster to go through the pages one by one (in a database, this is "poor selectivity").
For a 10-page book, it makes no sense to make an index, as you may end up with a 10-page book prefixed by a 5-page index, which is just silly - just scan the 10 pages and be done with it.
The index also needs t...
How to update npm
...all n module of npm:
sudo npm install -g n
3) Begin the installation by selecting the version of node to install: stable or latest, we will use stable here:
sudo n stable
4) Check the version of node:
node -v
5) Check the version of npm:
npm -v
...
Xcode 6 - How to pick signing certificate/provisioning profile for Ad-Hoc distribution?
...ple.com and find the distribution provisioning profile you want to use.
2) Select it, click "Edit", re-name the profile, and click "Generate".
3) Download the provisioning profile to the Desktop and drag it onto the Xcode 6 icon.
4) Re-start Xcode 6.
5) Open the organizer window and click "Submit" o...
Case in Select Statement
I have an SQL statement that has a CASE from SELECT and I just can't get it right. Can you guys show me an example of CASE where the cases are the conditions and the results are from the cases. For example:
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SQL Query Where Field DOES NOT Contain $x
...t is meant to be used in subqueries or with predefined lists:
-- subquery
SELECT a FROM x WHERE x.b NOT IN (SELECT b FROM y);
-- predefined list
SELECT a FROM x WHERE x.b NOT IN (1, 2, 3, 6);
If you are searching a string, go for the LIKE operator (but this will be slow):
-- Finds all rows where...
How to see the CREATE VIEW code for a view in PostgreSQL?
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select pg_get_viewdef('viewname', true)
A list of all those functions is available in the manual:
http://www.postgresql.org/docs/current/static/functions-info.html
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Jquery selector input[type=text]')
I wrote a code that basically selects all input type=text element like this:
4 Answers
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Select objects based on value of variable in object using jq
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Adapted from this post on Processing JSON with jq, you can use the select(bool) like this:
$ jq '.[] | select(.location=="Stockholm")' json
{
"location": "Stockholm",
"name": "Walt"
}
{
"location": "Stockholm",
"name": "Donald"
}
...