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Query Variables

What is a variable in GraphQL context?

GraphQL has a first-class way to factor dynamic values out of the query, and pass them as a separate dictionary. These values are called variables. In our case, we are defining the object to be inserted as a mutation.

So let's define the graphql mutation to be used.

Open src/components/Todo/TodoInput.tsx and add the following code:

githubsrc/components/Todo/TodoInput.tsx
import * as React from 'react';
+ import { gql } from "@apollo/client";
+ const ADD_TODO = gql `
+ mutation insert_todos($todo: String!, $isPublic: Boolean!) {
+ insert_todos(objects: {title: $todo, is_public: $isPublic}) {
+ affected_rows
+ returning {
+ id
+ title
+ is_completed
+ }
+ }
+ }
+ `;
const TodoInput = ({isPublic=false}) => {
const [todoInput, setTodoInput] = React.useState('');
return (
<form className="formInput" onSubmit={(e) => {
e.preventDefault();
// add todo
}}>
<input
className="input"
placeholder="What needs to be done?"
value={todoInput}
onChange={e => (setTodoInput(e.target.value))}
/>
<i className="inputMarker fa fa-angle-right" />
</form>
);
};
export default TodoInput;

What does this mutation do?

The mutation inserts into todos table with the $todo and $isPublic variables being passed.

Awesome! We have defined our first graphql mutation.

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