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SQL “select where not in subquery” returns no results
...MySQL
There are three ways to do such a query:
LEFT JOIN / IS NULL:
SELECT *
FROM common
LEFT JOIN
table1 t1
ON t1.common_id = common.common_id
WHERE t1.common_id IS NULL
NOT EXISTS:
SELECT *
FROM common
WHERE NOT EXISTS
(
SELECT NULL
FROM ...
Saving enum from select in Rails 4.1
...num.
I changed the input to be the following:
f.input :color, :as => :select, :collection => Wine.colors.keys.to_a
Which generated the following HTML:
<select id="wine_color" name="wine[color]">
<option value=""></option>
<option value="red">red</option>
...
Select all contents of textbox when it receives focus (Vanilla JS or jQuery)
What is a Vanilla JS or jQuery solution that will select all of the contents of a textbox when the textbox receives focus?
...
DISTINCT for only one column
...
If you are using SQL Server 2005 or above use this:
SELECT *
FROM (
SELECT ID,
Email,
ProductName,
ProductModel,
ROW_NUMBER() OVER(PARTITION BY Email ORDER BY ...
How do I select an entire row which has the largest ID in the table?
...
You could use a subselect:
SELECT row
FROM table
WHERE id=(
SELECT max(id) FROM table
)
Note that if the value of max(id) is not unique, multiple rows are returned.
If you only want one such row, use @MichaelMior's answer,
SELEC...
Can you have if-then-else logic in SQL? [duplicate]
I need to do select data from a table based on some kind of priority like so:
7 Answers
...
Which selector do I need to select an option by its text?
I need to check if a <select> has an option whose text is equal to a specific value.
16 Answers
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SQL Server 2008: How to query all databases sizes?
...
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...
Select values from XML field in SQL Server 2008
...
Given that the XML field is named 'xmlField'...
SELECT
[xmlField].value('(/person//firstName/node())[1]', 'nvarchar(max)') as FirstName,
[xmlField].value('(/person//lastName/node())[1]', 'nvarchar(max)') as LastName
FROM [myTable]
...
Entity Framework select distinct name
...
Using lambda expression..
var result = EFContext.TestAddresses.Select(m => m.Name).Distinct();
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