c pointer to struct issue - c

Question

The following code is giving me an error at the arrow in the second to last statement. I have no idea why this is . Could someone please tell me why?
I have no idea where to even begin. I thought it is correct but there is some issue.
/*
* File: newmain.c
* Author: user1
*
* Created on May 26, 2015, 4:30 PM
*/
#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
/*
*
*/
#ifndef KEYTYPE
#define KEYTYPE char *
#endif
#ifndef VALUETYPE
#define VALUETYPE double
#endif
#ifndef TYPE
#define TYPE struct association
//# define TYPE int
#endif
struct association
{
KEYTYPE key;
VALUETYPE value;
};
struct DynArr
{
TYPE *data; /* pointer to the data array */
//struct association *data;
int size; /* Number of elements in the array */
int capacity; /* capacity ofthe array */
};
int main(int argc, char** argv) {
struct DynArr *da;
da = malloc(sizeof(struct DynArr));
assert(da!= 0);
da->capacity = 2;
da->data = malloc(sizeof(TYPE) * da->capacity);
assert(da->data != 0);
da->size = 0;
if(da->data[0]->key == 2) //test.c:58:10: error: invalid type argument of ‘->’ (have ‘struct DynArr’) <<<<<<<<<<<<<<<<<<
return (EXIT_SUCCESS);
}

Answer 1

You are using the wrong operator, your instance of struct DynArr is not a pointer, hence you must use the . operator.
struct DynArr da;
/* This is also wrong because `capacity' has not been initialized yet! */
assert(da.capacity > 0);
/* ^ it's not a poitner */
and in all the other cases the same.
When the instance is a poitner of struct, like
struct DynArr da;
struct DynArr *pda;
pda = &da;
pda->capacity = 0;
/* ^ it's correct here */
EDIT:
After you edited your question I can see the problem
if(da->data[0]->key == 2)
da->data is of type TYPE * and you are dereferencing a pointer to it's first element in da->data[0], so it's no longer of type TYPE * i.e. not a pointer, so you need
if(da->data[0].key == 2)