Syntax
------

_rowid

Description
-----------

The _rowid pseudo column is mapped to the primary key in the related table.
This can be used as a replacement of the rowid pseudo column in other
databases. Another usage is to simplify sql queries as one doesn't have to
know the name of the primary key.

Examples
--------

create table t1 (a int primary key, b varchar(80));
insert into t1 values (1,"one"),(2,"two");
select * from t1 where _rowid=1;

+---+------+
| a | b    |
+---+------+
| 1 | one  |
+---+------+

update t1 set b="three" where _rowid=2;
select * from t1 where _rowid>=1 and _rowid<=10;

+---+-------+
| a | b     |
+---+-------+
| 1 | one   |
| 2 | three |
+---+-------+

URL: https://mariadb.com/kb/en/_rowid/