mysql - Designing flexible schema design in SQL -

i want design flexible schema design. when flexible schema design mean there different tables in database school, hospital, police stations.

now want write single proc in entity type (school, hospital, police station) passed parameter. these tables have different column names. thinking of keeping column need select each table in separate mapping table tell me columns need select different tables.

also store columns on basis of data needs filtered out in same mapping table. correct db design? can lead bottlenecks when data size or number of entities increase?

• i know classic case use non-relational dbs mongo due restrictions have use mysql.

if select * , load hash (associative array), can column names data.

(this 1 of few cases * "ok" use.)