What is metadata?

What is metadata?

It is a descriptive information about the database structure and connections.

e.g.

o Who is connected to the database?
o Is the database read only?
o What are the valid data types for the database
o What is the data type of the column.
o How does the database vendor deals with the stored procedure?
o How does the database handle cursor across rollback and commit?
o How many columns were retrieved in each row of the result?
o What is the SQL type, column name?
o What is the table name?
o How many decimal digits does a column have?