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How can I retrieve Id of inserted entity using Entity framework? [closed]
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It is pretty easy. If you are using DB generated Ids (like IDENTITY in MS SQL) you just need to add entity to ObjectSet and SaveChanges on related ObjectContext. Id will be automatically filled for you:
using (var context = new MyContext())
{
context.MyEntities.Add(myNewObject);
context.SaveCh...
Favorite (Clever) Defensive Programming Best Practices [closed]
... to make your code do things it isn't supposed to do. See Buffer Overflow, SQL Injection. Nothing fails faster than a web page under XSS but it ain't pretty
– Jorge Córdoba
Jan 29 '09 at 17:45
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“#include” a text file in a C program as a char[]
... Thanks, I chose the method proposed here to embed long fragments of sql into my C++ 11 code. This allows me to keep the SQL cleantly separated into its own files, and edit them with appropriate syntax checking, highlighting etc.
– YitzikC
Jan 29 '17 at 2...
How do I view the SQLite database on an Android device? [duplicate]
I have a set of data in an SQLite database. I need to view the database on a device. How do I do that?
19 Answers
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Laravel Schema onDelete set null
...to set proper onDelete constraint on a table in Laravel. (I'm working with SqLite)
4 Answers
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Postgresql - change the size of a varchar column to lower length
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There's a description of how to do this at Resize a column in a PostgreSQL table without changing data. You have to hack the database catalog data. The only way to do this officially is with ALTER TABLE, and as you've noted that change will lock and rewrite the entire table while it's running....
Dump a mysql database to a plaintext (CSV) backup from the command line
I'd like to avoid mysqldump since that outputs in a form that is only convenient for mysql to read. CSV seems more universal (one file per table is fine). But if there are advantages to mysqldump, I'm all ears. Also, I'd like something I can run from the command line (linux). If that's a mysql s...
How to set a default value for a datetime column to record creation time in a migration?
...the model will set the current time in the model.
You can also place some sql code in the migration for setting the default value at the database level, something like:
execute 'alter table foo alter column starts_at set default now()'
Setting something like this:
create_table :foo do |t|
t.d...
connecting to MySQL from the command line
How can you connect to MySQL from the command line in a Mac? (i.e. show me the code)
6 Answers
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Is there any performance gain in indexing a boolean field?
...an index, if you have too many records it doesn't use the index anyways.
MySQL not using index when checking = 1 , but using it with = 0
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