Solution for overloaded operator constraint in .NET generics

There is no immediate answer; operators are static, and cannot be expressed in constraints – and the existing primatives don’t implement any specific interface (contrast to IComparable[<T>] which can be used to emulate greater-than / less-than). However; if you just want it to work, then in .NET 3.5 there are some options… I have put …

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Show all the constraints of all tables in database

Use the information_schema.table_constraints table to get the names of the constraints defined on each table: select * from information_schema.table_constraints where constraint_schema=”YOUR_DB” Use the information_schema.key_column_usage table to get the fields in each one of those constraints: select * from information_schema.key_column_usage where constraint_schema=”YOUR_DB” If instead you are talking about foreign key constraints, use information_schema.referential_constraints: select * from …

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How do you constrain a template to only accept certain types

This typically is unwarranted in C++, as other answers here have noted. In C++ we tend to define generic types based on other constraints other than “inherits from this class”. If you really wanted to do that, it’s quite easy to do in C++11 and <type_traits>: #include <type_traits> template<typename T> class observable_list { static_assert(std::is_base_of<list, T>::value, …

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SQL-script: How to write ALTER statements to set Primary key on an existing table?

drop constraint and recreate it alter table Persion drop CONSTRAINT <constraint_name> alter table Persion add primary key (persionId,Pname,PMID) edit: you can find the constraint name by using the query below: select OBJECT_NAME(OBJECT_ID) AS NameofConstraint FROM sys.objects where OBJECT_NAME(parent_object_id)=’Persion’ and type_desc LIKE ‘%CONSTRAINT’