How to handle where clause in graphql schema?

by cortez.connelly , in category: Javascript , 3 months ago

How to handle where clause in graphql schema?

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1 answer

by raven_corwin , 3 months ago

@cortez.connelly 

In GraphQL, you can use arguments to pass input values to the resolver functions of your schema queries. This allows you to filter, sort, limit, and paginate the data you receive from your API.


Here is an example of how you can handle a "where" clause in a GraphQL schema:

  1. Define the schema:
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type Query {
  users(where: UserWhereInput): [User]
}

input UserWhereInput {
  name: String
  age: Int
}


  1. Implement the resolver function:
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const resolvers = {
  Query: {
    users: (_, { where }, context) => {
      let users = getUsersFromDatabase();

      if (where.name) {
        users = users.filter(user => user.name === where.name);
      }

      if (where.age) {
        users = users.filter(user => user.age === where.age);
      }

      return users;
    },
  },
};


  1. Query the data with the "where" clause:
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query {
  users(where: { name: "Alice", age: 30 }) {
    name
    age
  }
}


By following these steps, you can easily handle a "where" clause in your GraphQL schema to filter the data returned by your queries based on input values.