Which are the methods in the mapper interface?

642

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What is a namenode? How many instances of namenode run on a hadoop cluster?

648

---

What do you mean by taskinstance?

755

---

How hdfa differs with nfs?

749

---

How a task is scheduled by a jobtracker?

682

---

How many maximum jvm can run on a slave node?

694

---

What are the two main parts of the hadoop framework?

670

---

What is the use of combiners in the hadoop framework?

625

---

What is the jobtracker?

639

---

What is the jobtracker and what it performs in a hadoop cluster?

645

---

How many instances of tasktracker run on a hadoop cluster?

689

---

Explain the use of tasktracker in the hadoop cluster?

642

---

How does a namenode handle the failure of the data nodes?

700

---

How is spark sql different from hql and sql?

273

---

Is there a module to implement sql in spark? How does it work?

300

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