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How to get a complete list of ticker symbols from Yahoo Finance? [closed]
... similar by using this URL:
http://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20yahoo.finance.industry%20where%20id%20in%20(select%20industry.id%20from%20yahoo.finance.sectors)&env=store%3A%2F%2Fdatatables.org%2Falltableswithkeys
It downloads a complete list of stock symbols usi...
How to open a web server port on EC2 instance
...asn't immediately clear to me from the linked instructions, but you should select "Custom TCP". Otherwise you won't be able to change the port.
– KKOrange
Dec 12 '19 at 1:39
a...
How to map calculated properties with JPA and Hibernate
...e float finalPrice;
Or even complex queries on other tables:
@Formula("(select min(o.creation_date) from Orders o where o.customer_id = id)")
private Date firstOrderDate;
Where id is the id of the current entity.
The following blog post is worth the read: Hibernate Derived Properties - Perform...
Search text in stored procedure in SQL Server
...t the schema name by adding SCHEMA_NAME(o.schema_id) AS Schema_Name to the select clause.
– patricus
Jul 7 '16 at 15:07
6
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Postgresql query between date ranges
... things become simpler if you use >= start AND < end.
For example:
SELECT
user_id
FROM
user_logs
WHERE
login_date >= '2014-02-01'
AND login_date < '2014-03-01'
In this case you still need to calculate the start date of the month you need, but that should be straight forw...
Vim: How to change the highlight color for search hits and quickfix selection
... background for highlighting search hits. The same pattern is used for the selected entry in the quickfix window.
3 Answers...
Using async/await for multiple tasks
...ything but waiting.
int[] ids = new[] { 1, 2, 3, 4, 5 };
Task.WaitAll(ids.Select(i => DoSomething(1, i, blogClient)).ToArray());
On the other hand, the above code with WaitAll also blocks the threads and your threads won't be free to process any other work till the operation ends.
Recommende...
Oracle “(+)” Operator
...dize OUTER joins.
The query would be re-written in ANSI-92 syntax as:
SELECT ...
FROM a
LEFT JOIN b ON b.id = a.id
This link is pretty good at explaining the difference between JOINs.
It should also be noted that even though the (+) works, Oracle recommends not using it:
Oracle re...
What is cardinality in MySQL?
...ow cardinality column with only 2 possible values as the index will not be selective enough to be used.
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What is PostgreSQL explain telling me exactly?
...ly 1 sentence of technical content: "• EXPLAIN works on any DML not just SELECT (ie UPDATE, DELETE, and INSERT)". My biggest misunderstanding is what "startup" time means, and that's not explained anywhere in these ~30 slides.
– Mark E. Haase
Feb 19 '16 at 15...