---
url: https://docs.fluxify.rest/concepts/evaluators.md
description: Build route decisions and database filters with conditions.
---

# Conditions and Evaluators

Conditions let a route make a decision or narrow a database query. The editor looks similar in both places, but the two uses solve different problems:

| Where you use it | What it does |
| --- | --- |
| **If Condition block** | Evaluates values in the running route and chooses the true or false path. |
| **Database blocks** | Builds the filter used to select, update, or delete database records. |

## If conditions: choose a route path

An **If Condition** compares values available to the current request—such as `input`, a route parameter, or a runtime variable. If the condition is true, the route follows its success branch; otherwise, it follows its false branch.

![If Condition editor showing an input check and comparison operators](/evaluators/if-conditions.png)

Use simple comparisons for common checks:

* Is this value equal to, greater than, or less than another value?
* Is a request field empty or present?
* Do several checks all need to pass (**AND**), or is any one sufficient (**OR**)?

Both sides of a comparison can be a literal value or a JavaScript value computed from the current request. Use the **JS** option when the value must be derived, for example `return input.age;`. For more involved rules, choose the **JS** operator and return the boolean result you want the block to use.

Keep an If Condition focused on a business decision. It is usually easier to understand than a large all-in-one script, and it makes the true and false paths visible on the canvas.

## Database conditions: filter records

Database blocks use conditions to describe which rows or documents they should act on. Start by selecting the database column or field to filter; the condition is then applied by the database as part of the query.

![Database condition editor selecting the id column and a dynamic JavaScript value](/evaluators/db-condition.png)

The comparison value can be:

| Value type | Example | Use it when |
| --- | --- | --- |
| **Literal** | `"active"`, `18`, `true` | The filter value is known when you build the route. |
| **JavaScript value** | `return userId;` | The value comes from the current request or an earlier block. |
| **Column reference** | Compare one SQL column with another | The comparison depends on data already in the same record. |

For SQL connections, column references are resolved as database columns rather than ordinary text. Use a literal when you mean the characters exactly as written. For dynamic values, use the JavaScript option instead of assembling raw query text.

The same comparison operators—equals, not equals, greater/less than and their inclusive forms—are available for database filters. Combine conditions with **AND** or **OR** to make the filter more specific or provide alternatives.

> **Tip:** Add only the conditions required to identify the intended records. A broad update or delete filter can affect more rows than expected.

## Choosing the right kind of condition

Use an **If Condition** when you are deciding where the route should go next. Use a **database condition** when you are deciding which records a database block should read or change. If you need both, filter the record first, then use an If Condition to decide how to respond to the result.

## Related pages

* [If Condition block](../blocks/if-condition.md)
* [DB Get Single](../blocks/db-get-single.md)
* [Blocks](./blocks.md)