Creación de Tablas

 En la implementación de SQLiteOpeneHelper se ejecutan las queries de creación de las tablas

override fun onCreate(db: SQLiteDatabase) {
    db.execSQL(Companion.CLIENTES_SQL_CREATE_ENTRIES)
    db.execSQL(Companion.PEDIDOS_SQL_CREATE_ENTRIES)
    db.execSQL(Companion.PRODUCTOS_SQL_CREATE_ENTRIES)
    db.execSQL(Companion.FACTURAS_SQL_CREATE_ENTRIES)
    db.execSQL(Companion.PEDIDO_PRDUCTO_SQL_CREATE_ENTRIES)

}

Para el caso de practica prouesto las queries fueron las siguientes

private const val CLIENTES_SQL_CREATE_ENTRIES =
    "CREATE TABLE IF NOT EXISTS ${FerreteriaContract.ClienteEntry.TABLE_NAME} (" +
            "${FerreteriaContract.ClienteEntry.COLUMN_NAME_CODIGO} INTEGER PRIMARY KEY AUTOINCREMENT," +
            "${FerreteriaContract.ClienteEntry.COLUMN_NAME_NOMBRE} TEXT,"+
            "${FerreteriaContract.ClienteEntry.COLUMN_NAME_DIRECCION} TEXT,"+
            "${FerreteriaContract.ClienteEntry.COLUMN_NAME_TELEFONO} INTEGER )"


private const val PRODUCTOS_SQL_CREATE_ENTRIES =
    "CREATE TABLE  IF NOT EXISTS ${FerreteriaContract.ProductoEntry.TABLE_NAME} (" +
            "${FerreteriaContract.ProductoEntry.COLUMN_NAME_CODIGO} INTEGER PRIMARY KEY AUTOINCREMENT," +
            "${FerreteriaContract.ProductoEntry.COLUMN_NAME_FABRICANTE} TEXT,"+
            "${FerreteriaContract.ProductoEntry.COLUMN_NAME_VALOR} DECIMAL,"+
            "${FerreteriaContract.ProductoEntry.COLUMN_NAME_COD_PEDIDO} INTEGER)"


private const val PEDIDOS_SQL_CREATE_ENTRIES =
    "CREATE TABLE IF NOT EXISTS ${FerreteriaContract.PedidoEntry.TABLE_NAME} (" +
            "${FerreteriaContract.PedidoEntry.COLUMN_NAME_CODIGO} INTEGER PRIMARY KEY AUTOINCREMENT," +
            "${FerreteriaContract.PedidoEntry.COLUMN_NAME_DESCRIPCION} TEXT,"+
            "${FerreteriaContract.PedidoEntry.COLUMN_NAME_FECHA} DATE,"+
            "${FerreteriaContract.PedidoEntry.COLUMN_NAME_COD_CLIENTE} INTEGER, "+
            "FOREIGN KEY (${FerreteriaContract.PedidoEntry.COLUMN_NAME_COD_CLIENTE}) "+
            "REFERENCES ${FerreteriaContract.ClienteEntry.TABLE_NAME} " +
            " (${FerreteriaContract.ClienteEntry.COLUMN_NAME_CODIGO}))"


private const val FACTURAS_SQL_CREATE_ENTRIES =
    "CREATE TABLE IF NOT EXISTS ${FerreteriaContract.FacturaEntry.TABLE_NAME} (" +
            "${FerreteriaContract.FacturaEntry.COLUMN_NAME_CODIGO} INTEGER PRIMARY KEY AUTOINCREMENT," +
            "${FerreteriaContract.FacturaEntry.COLUMN_NAME_FECHA} DATE,"+
            "${FerreteriaContract.FacturaEntry.COLUMN_NAME_VALOR} DECIMAL,"+
            "${FerreteriaContract.FacturaEntry.COLUMN_NAME_COD_PEDIDO} INTEGER, "+
            "FOREIGN KEY (${FerreteriaContract.FacturaEntry.COLUMN_NAME_COD_PEDIDO}) " +
            "REFERENCES ${FerreteriaContract.PedidoEntry.TABLE_NAME} " +
            "(${FerreteriaContract.PedidoEntry.COLUMN_NAME_CODIGO}));"