FunctionContext [] contexts = hashTable.get(keyTuple);
for(int i = 0; i < aggFunctions.length; i++) {
aggFunctions[i].merge(contexts[i], inSchema, tuple);
}
} else { // if the key occurs firstly
FunctionContext contexts [] = new FunctionContext[aggFunctionsNum];
for(int i = 0; i < aggFunctionsNum; i++) {
contexts[i] = aggFunctions[i].newContext();
aggFunctions[i].merge(contexts[i], inSchema, tuple);
}
hashTable.put(keyTuple, contexts);