mysql - Database design to create tables on the fly

Question

I need to create dynamic tables in the database on the fly. For example, in the database I will have tables named:

Table
Column
DataType
TextData
NumberData
DateTimedata
BitData

Here I can add a table in the table named table, then I can add all the columns to that table in the columns table and associate a datatype to each column.

Basically I want to create tables without actually creating a table in the database. Is this even possible? If so, can you direct me to the right place so I can research? Also, I would prefer sql server or any free database software.

Thanks

Answer 1

What you are describing is an entity-attribute-value model (EAV). It is a very poor way to design a data model.

Although the data model is quite flexible, querying such a data model is quite complicated. You frequently end up having to self-join a table n times if you want to select or filter on n different attributes. That gets slow rather slow and becomes rather hard to optimize relatively quickly.

Plus, you generally end up building a lot of functionality that the database or your ORM would provide.