Use variables to simplify queries and mutations

Variables let you create dynamic code.

Instead of entering static values for every argument, define and use a variable. You can update the variable anytime to push changes for that value everywhere in your code.

This simplifies code and makes it much easier to maintain.

How to define and enter variables

In GraphQL, variables are JSON objects. You can use variables for both queries and mutations.

Here’s an example. First, we’ll replace the static value in the query with $variable.

query queryName ($variable : type) {
  fieldName1
  fieldName2 (filter: {field1 {in : $variable}}) {
    field1
    field2
  }
}

We replaced the value for the in field in fieldName2 with the $variable.

Then declare the variable and its value in a separate variable dictionary:

{
  variable: “value”
}

Now, any time you update the variable’s value, the change is reflected wherever you used the variable.

Learn more about variables from GraphQL.org.