Inmemory Cache implementation in using Apollo client

hi, I am a newbie in graphql and cahing implementations.
I need to cache the values for some field resolvers that make a database call. I don't want to cache all the fileds or queries with theier response.
Here is my resolver in which a DB call is made: -
`
const resolvers={

Employee: {
    empId: async (obj, params, ctx, resolverInfo) => {
        
        return db.one('SELECT iuid FROM iuidtest WHERE empid = $1', [999])
        .then(iuidtest => {
            return iuidtest.iuid; 
        })
    
    }
}`

I am using inmemory cache over here:-
const httpLink = createHttpLink({
uri: 'http://127.0.0.1:3003/',
fetch: fetch
})
const client = new ApolloClient({
link: httpLink,
cache: new InMemoryCache()
});
This is my graphql server hosted on localhost: -

const server = new ApolloServer({ schema, context: { driver } });
server.listen(3003, '127.0.0.1').then(({ url }) => {
console.log(GraphQL API ready at ${url});
});

For now I'm trying to cache the whole query response but that does not seem to be working as I'm getting the same delay in response as before.
Here is my query: -
{
employee(first:20000)
{
empId
iuid
name

}

}
While using the readQuery method also i'm nt ableto validate by making the query call to cache also.
Any help would be appreciated.