# Condition Builder

You can use condition builders to create condition statements within your workflow. For example, you can use it to control the flow using the While Loop or Conditions block. Also, you can add a condition button by clicking "Add condition".

### Value <a href="#value" id="value"></a>

#### Value <a href="#value-1" id="value-1"></a>

You can write expressions within the text field for the value you want to compare.

**Value prefix**

This prefix is a convention that serves to specify the data type of a value. You can use it to convert a value to the corresponding data type. For instance, you can use the "string::" prefix to convert a value to a string type and "number::" to convert a value to a numeric type.

Available prefix:

* `string::`: converts the value to a string.
* `json::`: converts the value to a JSON.
* `number::`: converts the value to a digit.
* `boolean::`: converts the value to a boolean.

#### Code <a href="#code" id="code"></a>

JavaScript expressions.

#### Data Exists <a href="#data-exists" id="data-exists"></a>

This checks if workflow data exists (table, variables, etc). E.g., checks variable name: `variables.name` or `variables@name`


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