Tables, indexes, columns etc. have naming restrictions such as they must begin with an alphabetic character. This document lists those rules.
Tables, indexes and columns are
named objects within a database. A DBMS name must begin
with an alphabetic character, after which any alphabetic, numeric or the _ (underscore)
character may be used. DBMS names are also limited to 64 characters in length.
Table names must be unique within a database, and columns and indexes must
have unique names within the table to which they belong. For the purposes
of uniqueness and identification, the names are folded before comparison,
so two columns named column_one and Column_ONE are
considered to have the same name.
Names in a database have no further restrictions.