SQL
Examples
Create a schema:  
```sql
CREATE SCHEMA s1;
```  
Create a schema if it does not exist yet:  
```sql
CREATE SCHEMA IF NOT EXISTS s2;
```  
Create table in the schemas:  
```sql
CREATE TABLE s1.t (id INTEGER PRIMARY KEY, other_id INTEGER);
CREATE TABLE s2.t (id INTEGER PRIMARY KEY, j VARCHAR);
```  
Compute a join between tables from two schemas:  
```sql
SELECT *
FROM s1.t s1t, s2.t s2t
WHERE s1t.other_id = s2t.id;
```