Tinker10:00. Each warehouse’s board is its own copy of the count.North 7/1, East 7/1, West 7/1
Chapter 1 of 7
One count, three copies
Larkspur’s stock count used to live in one database. Now each of its three warehouses keeps its own copy, so every region answers fast.
This chapter: When North sells a hinge, what do the other copies show?
About this chapter
You will learn
- A replica is a copy of the same data in another place
- Changes reach the other copies after a delay
- Why a copy can answer with an old count
Words you’ll meet
- Replica
- One copy of the same data, kept in another place: here, each warehouse’s stock count.
- Replication lag
- The time a change takes to reach the other replicas.
- Stale
- Older than the newest change: a count that hasn’t heard about the latest sale.
Step 1 of 5
Each warehouse keeps a of the stock count. All three say 7 hinges.
Move the clock to 10:01.
New to databases? Databases & indexes comes first.