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The model backing the context has changed since the database was created
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Now it's:
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
Database.SetInitializer<YourDbContext>(null);
base.OnModelCreating(modelBuilder);
}
in your YourDbContext.cs file.
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SQLAlchemy: cascade delete
...SCADE that you set up. This is because it relies on those foreign keys to know which child rows to delete. Once SqlAlchemy has set them all to NULL, the database can't delete them. Setting the passive_deletes=True prevents SqlAlchemy from NULLing out the foreign keys.
You can read more about passive...
Read environment variables in Node.js
...he top of your application entry file:
require('dotenv').config();
Done. Now you can access your environment variables with process.env.ENV_NAME.
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How do you set a default value for a MySQL Datetime column?
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IMPORTANT EDIT:
It is now possible to achieve this with DATETIME fields since MySQL 5.6.5, take a look at the other post below...
Previous versions can't do that with DATETIME...
But you can do it with TIMESTAMP:
mysql> create table test (st...
Set select option 'selected', by value
I have a select field with some options in it. Now I need to select one of those options with jQuery. But how can I do that when I only know the value of the option that must be selected?
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What's the need of array with zero elements?
...s Aniket said), but it was standardized in C99. The standard format for it now is:
struct bts_action {
u16 type;
u16 size;
u8 data[];
} __attribute__ ((packed)); /* Note: the __attribute__ is irrelevant here */
Note that you don't mention any size for the data field. Note also that...
Efficiently convert rows to columns in sql server
...nt, PostalCode, LastName, AccountNumber)
) piv;
See Demo.
Pivot with unknown number of columnnames
If you have an unknown number of columnnames that you want to transpose, then you can use dynamic SQL:
DECLARE @cols AS NVARCHAR(MAX),
@query AS NVARCHAR(MAX)
select @cols = STUFF((SELECT ',...
JavaScript - get the first day of the week from current date
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Using the getDay method of Date objects, you can know the number of day of the week (being 0=Sunday, 1=Monday, etc).
You can then subtract that number of days plus one, for example:
function getMonday(d) {
d = new Date(d);
var day = d.getDay(),
diff = d.getDate()...
How can I reliably get an object's address when operator& is overloaded?
...regular member functions of a template class, thanks for pointing it out. (Now I just need to figure out what is the use of the overload, any tip ?)
– Matthieu M.
Jun 27 '11 at 16:50
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Error to install Nokogiri on OSX 10.9 Maverick?
... I ran xcode-select --install before the brew install and all works now.
– Quickredfox
Nov 20 '13 at 0:10
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