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How to publish a website made by Node.js to Github Pages?
....It contains pure html files.So everything you see on the link is actually from the gh-pages branch.
– Akshat Jiwan Sharma
Apr 17 '13 at 18:26
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Fastest check if row exists in PostgreSQL
...
Use the EXISTS key word for TRUE / FALSE return:
select exists(select 1 from contact where id=12)
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Calculate a Running Total in SQL Server
... somewhat limited.
Oracle (and ANSI-SQL) allow you to do things like:
SELECT somedate, somevalue,
SUM(somevalue) OVER(ORDER BY somedate
ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW)
AS RunningTotal
FROM Table
SQL Server gives you no clean solution to this problem. My ...
How to delete duplicate rows in SQL Server?
... are deleted (or updated), therefore just change the DELETE FROM CTE... to SELECT * FROM CTE:
WITH CTE AS(
SELECT [col1], [col2], [col3], [col4], [col5], [col6], [col7],
RN = ROW_NUMBER()OVER(PARTITION BY col1 ORDER BY col1)
FROM dbo.Table1
)
DELETE FROM CTE WHERE RN > 1
DEMO (re...
How to create a MySQL hierarchical recursive query
... or self-joins.
MySQL 8+
with recursive cte (id, name, parent_id) as (
select id,
name,
parent_id
from products
where parent_id = 19
union all
select p.id,
p.name,
p.parent_id
from products p
inner join cte
...
SELECT INTO Variable in MySQL DECLARE causes syntax error?
I´d like to SELECT a single value into a variable. I´d tried to following:
11 Answers
...
SSH to Elastic Beanstalk instance
... region.
Configure Security Group
In the AWS console, open the EC2 tab.
Select the relevant region and click on Security Group.
You should have an elasticbeanstalk-default security group if you have launched an Elastic Beanstalk instance in that region.
Edit the security group to add a rule for S...
Delete duplicate records in SQL Server?
...r the dupes by empId, and delete all but the first one.
delete x from (
select *, rn=row_number() over (partition by EmployeeName order by empId)
from Employee
) x
where rn > 1;
Run it as a select to see what would be deleted:
select *
from (
select *, rn=row_number() over (partition b...
MySQL Conditional Insert
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If your DBMS does not impose limitations on which table you select from when you execute an insert, try:
INSERT INTO x_table(instance, user, item)
SELECT 919191, 123, 456
FROM dual
WHERE NOT EXISTS (SELECT * FROM x_table
WHERE user = ...
How to randomly select an item from a list?
...ults, but depending on the start seed, it's not guaranteed. If you want to select n distinct random elements from a list lst, use random.sample(lst, n)
– Graham
Dec 23 '18 at 17:02
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