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How to get all Errors from ASP.Net MVC modelState?

... During debugging I find it useful to put a table at the bottom of each of my pages to show all ModelState errors. <table class="model-state"> @foreach (var item in ViewContext.ViewData.ModelState) { if (item.Value.Errors.Any()) { ...
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Why use multiple columns as primary keys (composite primary key)

... Another example of compound primary keys are the usage of Association tables. Suppose you have a person table that contains a set of people and a group table that contains a set of groups. Now you want to create a many to many relationship on person and group. Meaning each person can belong t...
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python list in sql query as parameter

... = [1,5,8] l = tuple(l) params = {'l': l} cursor.execute('SELECT * FROM table where id in %(l)s',params) I hope this helped !!! share | improve this answer | follow ...
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Return number of rows affected by UPDATE statements

... CREATE PROCEDURE UpdateTables AS BEGIN -- SET NOCOUNT ON added to prevent extra result sets from -- interfering with SELECT statements. SET NOCOUNT ON; DECLARE @RowCount1 INTEGER DECLARE @RowCount2 INTEGER DECLARE @RowCount3...
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What is RSS and VSZ in Linux memory management

...g work? and in particular that the OS can allocate virtual memory via page tables / its internal memory book keeping (VSZ virtual memory) before it actually has a backing storage on RAM or disk (RSS resident memory). Now to observe this in action, let's create a program that: allocates more RAM t...
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How to efficiently build a tree from a flat structure?

... Store IDs of the objects in a hash table mapping to the specific object. Enumerate through all the objects and find their parent if it exists and update its parent pointer accordingly. class MyObject { // The actual object public int ParentID { get; set; ...
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How do I change column default value in PostgreSQL?

... 'SET' is forgotten ALTER TABLE ONLY users ALTER COLUMN lang SET DEFAULT 'en_GB'; share | improve this answer | follow ...
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How does collections.defaultdict work?

... Neither. 0 is immutable - in CPython all values from -5 to 256 are cached singletons but this is implementation-specific behaviour - in both cases a new instance is "created" each time with int() or list(). That way, d[k].append(v) can work wi...
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How to force child div to be 100% of parent div's height without specifying parent's height?

...this with CSS in a browser compatible way is not trivial (but trivial with tables) so find yourself an appropriate pre-packaged solution. Also, the answer varies on whether you want 100% height or equal height. Usually it's equal height. If it's 100% height the answer is slightly different. ...
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How do you check “if not null” with Eloquent?

... If you wanted to use the DB facade: DB::table('table_name')->whereNotNull('sent_at')->get(); share | improve this answer | follow ...