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Why does AngularJS include an empty option in select?
...efined in the specification at http://docs.angularjs.org/api/ng.directive:select , I still get an empty option as the first child of select element.
...
Using group by on multiple columns
..., to do with who is attending what subject at a university:
Table: Subject_Selection
+---------+----------+----------+
| Subject | Semester | Attendee |
+---------+----------+----------+
| ITB001 | 1 | John |
| ITB001 | 1 | Bob |
| ITB001 | 1 | Mickey |
| ITB001 ...
Finding duplicate values in a SQL table
...
SELECT
name, email, COUNT(*)
FROM
users
GROUP BY
name, email
HAVING
COUNT(*) > 1
Simply group on both of the columns.
Note: the older ANSI standard is to have all non-aggregated columns in the GROUP BY ...
What are DDL and DML?
...als with data
manipulation, and includes most common SQL statements such SELECT,
INSERT, UPDATE, DELETE etc, and it is used to store, modify, retrieve,
delete and update data in database.
SELECT – retrieve data from the a database
INSERT – insert data into a table
UPDATE – up...
What is the difference between Google App Engine and Google Compute Engine?
...IT (April 2017):
Cloud Functions (currently in beta) is the next level up from App Engine in terms of abstraction - no instances! It allows developers to deploy bite-size pieces of code that execute in response to different events, which may include HTTP requests, changes in Cloud Storage, etc.
Th...
How to return only the Date from a SQL Server DateTime datatype
...
On SQL Server 2008 and higher, you should CONVERT to date:
SELECT CONVERT(date, getdate())
On older versions, you can do the following:
SELECT DATEADD(dd, 0, DATEDIFF(dd, 0, @your_date))
for example
SELECT DATEADD(dd, 0, DATEDIFF(dd, 0, GETDATE()))
gives me
2008-09-22 00:...
Get top 1 row of each group
...
;WITH cte AS
(
SELECT *,
ROW_NUMBER() OVER (PARTITION BY DocumentID ORDER BY DateCreated DESC) AS rn
FROM DocumentStatusLogs
)
SELECT *
FROM cte
WHERE rn = 1
If you expect 2 entries per day, then this will arbitrarily pick one...
Multithreading: What is the point of more threads than cores?
...ads running at a time? Wouldn't they just be stealing time (CPU Resources) from each other?
17 Answers
...
Find rows that have the same value on a column in MySQL
...sses and how many times they're used, with the most used addresses first.
SELECT email,
count(*) AS c
FROM TABLE
GROUP BY email
HAVING c > 1
ORDER BY c DESC
If you want the full rows:
select * from table where email in (
select email from table
group by email having count(*) &g...
Detect if value is number in MySQL
...
This should work in most cases.
SELECT * FROM myTable WHERE concat('',col1 * 1) = col1
It doesn't work for non-standard numbers like
1e4
1.2e5
123. (trailing decimal)
share
...