SQL
Using Double Equality Sign for Comparison
DuckDB supports both `=` and `==` for quality comparison, while Postgres only supports `=`.  
```sql
SELECT 1 == 1 AS t;
```  
DuckDB returns:  
```text
┌─────────┐
│    t    │
│ boolean │
├─────────┤
│ true    │
└─────────┘
```  
Postgres returns:  
```console
postgres=# SELECT 1 == 1 AS t;
ERROR:  operator does not exist: integer == integer
LINE 1: SELECT 1 == 1 AS t;
```  
Note that the use of `==` is not encouraged due to its limited portability.