> ## Documentation Index
> Fetch the complete documentation index at: https://docs.usedatabrain.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Complex Filter

> Complex Filter Feature: Quick Instruction Manual

### Accessing Complex Filter

1. Click on the filter (funnel) icon.
2. Select **"+ Add Filter"**.
3. Choose **"Complex Filter"** from the list.
4. A modal will appear to add the custom **WHERE** clause.

<Frame>
  <img src="https://mintcdn.com/databrainlabs-bef6850a/3OVuv1yincv0D6pa/images/guides/complex-filter.gif?s=50d0ff8c91b1004f5e8b1c10cda44231" alt="Demonstration of accessing and opening the complex filter modal in Databrain" width="1633" height="918" data-path="images/guides/complex-filter.gif" />
</Frame>

### Using Complex Filter without Custom SQL

* You can write complex filters for any table that is part of the dimensions/measures.
* Example columns in Dimensions/Measures: `"public_table1"."country"`, `"public_table2"."location"`, `"public_table1"."population"`
  * For the above, below will be our generated SQL:

```sql theme={"dark"}
SELECT
  "public_table1"."country" AS "country",
  "public_table2"."location" AS "location",
  "public_table1"."population" AS "population"
FROM
  "public"."table1" AS "public_table1"
  INNER JOIN "public"."table2" AS "public_table2" ON "public_table2"."code" = "public_table1"."code"
LIMIT 100
```

* Example Complex Filter that you can write:

```sql theme={"dark"}
"public_table2"."location" = UPPER("public_table1"."country")
"public_table1"."population" > 100000
```

### Using Complex Filter with Custom SQL

* When writing a custom SQL query, the complex filter can only address columns of the table `"dbn_sql_table"`.
  * Example Custom SQL that you write:

```sql theme={"dark"}
SELECT
  "country" AS "country",
  "population" AS "population"
FROM
  "public"."table"
```

* The SQL generated by us:

```sql theme={"dark"}
SELECT
  "country" AS "country",
  "population" AS "population"
FROM
(
  SELECT
    "country" AS "country",
    "population" AS "population"
  FROM
    "public"."table"
) AS "dbn_sql_table"
```

**Example Complex Filter with Custom SQL:**

* Example Complex Filter that you can write:

```sql theme={"dark"}
"dbn_sql_table"."population" > 100000
"dbn_sql_table"."location" = 'Japan'
```

<Check>
  You’ve successfully applied a Complex Filter in Databrain! Your advanced filtering logic is now in effect, enabling deeper and more precise data analysis.
</Check>