MongoDB比較運算子用於測試等於或不等於，還有其它更高階的運算子。
在WHERE子句中使用比較運算子來確定要選擇的記錄。以下是可以在MariaDB中使用的比較運算子的列表：
語法及範例 -
| 編號 | 比較運算子 | 描述 | 範例 |
|---|---|---|---|
| 1 | = |
比較等於 | select * from students where id=100 |
| 2 | <=> |
比較等於(安全比較NULL值) |
select * from students where student_name<=>'Maxsu' |
| 3 | <> |
比較不等於 | select * from students where student_name<>'Maxsu' |
| 4 | != |
比較不等於 | select * from students where student_name!='Maxsu' |
| 5 | > |
比較大於 | select * from students where student_id>5 |
| 6 | >= |
比較大於或等於 | select * from students where student_id>=5 |
| 7 | < |
比較小於 | select * from students where student_id<5 |
| 8 | <= |
比較小於或等於 | select * from students where student_id<=5 |
| 9 | in ( ) |
匹配列表中的值 | select * from students where student_id IN(1,3,6) |
| 10 | not |
否定一個條件 | select * from students where student_id NOT IN(1,3,6) |
| 11 | between |
匹配在一個範圍內(含) | select * from students where student_id between 1 AND 3) |
| 12 | is null |
判斷是否為NULL值 |
select * from students where student_address IS NULL |
| 13 | is not null |
判斷是否為非NULL值 |
select * from students where student_address IS NOT NULL |
| 14 | like |
與%和_模式匹配 |
select * from students where student_name LIKE 'Ma%' |
| 15 | exists |
如果子查詢返回至少一行，則滿足條件。 | — |