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How do I use regex in a SQLite query?
...ite manager. You need to invoke it slightly differently though, like this: SELECT * FROM table WHERE column regexp("myregexp")
– Tristan
May 30 '14 at 17:16
...
What is the difference between UNION and UNION ALL?
...want the duplicates (especially when developing reports).
UNION Example:
SELECT 'foo' AS bar UNION SELECT 'foo' AS bar
Result:
+-----+
| bar |
+-----+
| foo |
+-----+
1 row in set (0.00 sec)
UNION ALL example:
SELECT 'foo' AS bar UNION ALL SELECT 'foo' AS bar
Result:
+-----+
| bar |
+---...
sql query to return differences between two tables
...colum C, here are the records, which are present in table A but not in B:
SELECT A.*
FROM A
LEFT JOIN B ON (A.C = B.C)
WHERE B.C IS NULL
To get all the differences with a single query, a full join must be used, like this:
SELECT A.*, B.*
FROM A
FULL JOIN B ON (A.C = B.C)
WHERE A.C IS NUL...
LINQ - Full Outer Join
...rst.ID equals last.ID into temp
from last in temp.DefaultIfEmpty()
select new
{
first.ID,
FirstName = first.Name,
LastName = last?.Name,
};
var rightOuterJoin =
from last in lastNames
join first in firstNames on last.ID equals first.ID into temp
fr...
How to open a specific port such as 9090 in Google Compute Engine
...hoose "Firewalls rules"
Choose "Create Firewall Rule"
To apply the rule to select VM instances, select Targets > "Specified target tags", and enter into "Target tags" the name of the tag. This tag will be used to apply the new firewall rule onto whichever instance you'd like. Then, make sure the ...
How to undo another user’s checkout in TFS?
...t-clicking the desired project, folder, or file in Source Control Explorer
Select Properties
Select the Security tab
Select the appropriate user or group in the Users and Groups section at the top
View the "Permissions for [user/group]:" section at the bottom
Deleting the workspace
tf workspace /...
How to flatten nested objects with linq expression
...
myBooks.SelectMany(b => b.Chapters
.SelectMany(c => c.Pages
.Select(p => b.Name + ", " + c.Name + ", " + p.Name)));
share
|
...
The type or namespace name 'DbContext' could not be found [closed]
... @Chris Dickinson, right click on the References item in the project and select Add Reference.... Then in the .NET tab, select System.Data.Entity. And if you want to use NuGet, right click on the References item and then select Add Library Package Reference... and in the Online tab, search for Ent...
Remove all spaces from a string in SQL Server
...
Simply replace it;
SELECT REPLACE(fld_or_variable, ' ', '')
Edit:
Just to clarify; its a global replace, there is no need to trim() or worry about multiple spaces for either char or varchar:
create table #t (
c char(8),
v varchar(8))...
How to set selected item of Spinner by value, not by position?
I have a update view, where I need to preselect the value stored in database for a Spinner.
25 Answers
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