Coding Guidelines

These are general rules for development in the system. As of 2018, we do not follow all of these exactly. These are more aspirations.

1. The TransactionContext object should always be the first argument to any function that takes it.

   Good Example

   ResultType CreateDatabase(concurrency::TransactionContext *txn,
                             const std::string &database_name);

   Bad Example

   ResultType CreateDatabase(const std::string &database_name,
                             concurrency::TransactionContext *txn);

2. Never use default values for function arguments. This prevents unexpected behavior and invalid invocations.

   Good Example

   void MyFunc(int arg1, int arg2);

   Bad Example

   void MyFunc(int arg1, int arg2 = 1234);

3. The order of catalog arguments to a function should go in the order of the catalog hierarchy (Database→Schema→Table→Index). Furthermore, you should not mix names with oids in arguments.

   Good Example

   void DoSomethingInCatalog(oid_t database_oid,
                             oid_t schema_oid,
                             oid_t table_oid);

   Bad Example

   void DoSomethingInCatalog(oid_t database_oid,
                             std::string table_name,
                             oid_t schema_oid);