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How to flatten nested objects with linq expression
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myBooks.SelectMany(b => b.Chapters
.SelectMany(c => c.Pages
.Select(p => b.Name + ", " + c.Name + ", " + p.Name)));
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Naming of ID columns in database tables
...!)and forget to change the alias in the join condition.
So you now have
select t1.field1, t2.field2, t3.field3
from table1 t1
join table2 t2 on t1.id = t2.table1id
join table3 t3 on t1.id = t3.table2id
when you meant
select t1.field1, t2.field2, t3.field3
from table1 t1
join table2 t2 on t1...
How can I insert values into a table, using a subquery with more than one result?
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You want:
insert into prices (group, id, price)
select
7, articleId, 1.50
from article where name like 'ABC%';
where you just hardcode the constant fields.
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Get table name by constraint name [duplicate]
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SELECT owner, table_name
FROM dba_constraints
WHERE constraint_name = <<your constraint name>>
will give you the name of the table. If you don't have access to the DBA_CONSTRAINTS view, ALL_CONSTRAINTS or US...
How do I disable text selection with CSS or JavaScript? [duplicate]
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<div
style="-moz-user-select: none; -webkit-user-select: none; -ms-user-select:none; user-select:none;-o-user-select:none;"
unselectable="on"
onselectstart="return false;"
onmousedown="return false;">
Blabla
</div>
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Build an iOS app without owning a mac? [closed]
...r virtual machine (the name is unimportant, I called it "Mac"). In "Type", select "Mac OS X" and in "Version" select "macOS 10.13 High Sierra (64 bit)" (the Mac version you will install on the virtual machine is actually Catalina, but VirtualBox doesn't have that option yet and it works just fine if...
Is it possible to insert multiple rows at a time in an SQLite database?
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This can be recast into SQLite as:
INSERT INTO 'tablename'
SELECT 'data1' AS 'column1', 'data2' AS 'column2'
UNION ALL SELECT 'data1', 'data2'
UNION ALL SELECT 'data1', 'data2'
UNION ALL SELECT 'data1', 'data2'
a note on performance
I originally used this technique to efficiently lo...
Install .ipa to iPad with or without iTunes
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In Xcode 5 open the organizer (Window > Organizer) and select "Devices" at the top. Your plugged in device should show up on the left hand side. Drag the IPA file over to that device.
In Xcode 6 and Xcode 7 open Devices (Window > Devices). Again your device should show up in ...
What is a stored procedure?
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CREATE PROCEDURE Users_GetUserInfo
@login nvarchar(30)=null
AS
SELECT * from [Users]
WHERE ISNULL(@login,login)=login
A benefit of stored procedures is that you can centralize data access logic into a single place that is then easy for DBA's to optimize. Stored procedures also have...
How to check if an option is selected?
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UPDATE
A more direct jQuery method to the option selected would be:
var selected_option = $('#mySelectBox option:selected');
Answering the question .is(':selected') is what you are looking for:
$('#mySelectBox option').each(function() {
if($(this).is(':selected')) ....