# Base de datos

```mermaid
erDiagram

Common{
    integer id PK "not null"
    integer procedure FK "not null Procedures"
    integer session FK "not null Sessions"
    datetime date_in "CK not null default now()"
    datetime date_out
}

_Common{
    integer id PK "not null"
    integer register FK "not null Entity"
    integer procedure FK "not null Procedures"
    integer session FK "not null Sessions"
    datetime date_in "CK not null default now()"
    datetime date_out
}

Databases{
    varchar(64) name UK "CK not null"
}

Procedures{
    integer database FK,UK "not null Database"
    varchar(64) name UK "CK not null"
}

Databases ||--|{ Procedures : is

```