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Why do we not have a virtual constructor in C++?
...uctor ends.In order for the constructor to be dispatched using the virtual table , there has to be an existing object with a pointer to the virtual table , but how can a pointer to the virtual table exist if the object still doesn't exist? :)
Logic reason
You use the virtual keyword when you want ...
Find document with array that contains a specific value
...nd that such solutions work so simply without needing JOINs and additional tables makes me wonder why I haven't started on Mongo sooner. But that's not to say either DBMS is superior over the other - it depends on your use case.
– Irvin Lim
Jun 18 '15 at 14:37
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How to install mongoDB on windows?
...st imagine an SQL server or Oracle Db with entirely different rows in same table? Is it possible in our relational DB table? This is how mongo works. I will show you how we can do that…
First I will show you how the data will look in a relational DB.
For example consider an Employee table and a S...
SQL how to increase or decrease one for a int column in one command
I have an Orders table which has a Quantity column. During check in or check out, we need to update that Quantity column by one. Is there a way to do this in one action or we have to get the existing value and then add or minus one on top of it?
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Is there an auto increment in sqlite?
I am trying to create a table with an auto-incrementing primary key in Sqlite3 . I am not sure if this is really possible, but I am hoping to only have to designate the other fields.
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How to list the properties of a JavaScript object?
...es, ES5 provides Object.getOwnPropertyNames (see its support in my compat. table — kangax.github.com/es5-compat-table)
– kangax
Oct 27 '10 at 2:43
2
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Entity Attribute Value Database vs. strict Relational Model Ecommerce
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What if you had a single table with indexes for text values 1-n, then in C# (in ram) map what you want to what you need. It would still work like an EAV, but the "matches" would be domain models. Sort of like a serialization, but you could use SQL ...
How to add a footer to a UITableView in Storyboard
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You can just drag a view to the bottom area of the tableView. You'll see in the hierarchy that it will be a subview of the tableview. You can then drag subviews such as labels and buttons there, adjust the height, etc.
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How to use Regular Expressions (Regex) in Microsoft Excel both in-cell and loops
...ing
E.g. a$ Last character must be lower case letter a
Precedence table:
Order Name Representation
1 Parentheses ( )
2 Multipliers ? + * {m,n} {m, n}?
3 Sequence & Anchors abc ^ $
4 Alternation |
Predefined Character Abbr...
Entity Framework Refresh context?
...ntities based on views from my Database and when I made an update over one table Entity that has navigation properties to views, the entity is update but the view don't refresh accord the new updates...just want to get again from the Db the data.
Thanks!
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