Faults and Partial FailuresFor single computer system, it is usually either fully functional or entirely broken. System prefe...

Concept of TransactionA transaction is a way for an application to group several reads and writes together into a logical uni...

Sometimes in VSCode, we want to “jump to declaration”, then IDE redirect us to a file with suffix .pyi, and all it contains a...

IntroThe main reason for wanting to partition data is scalability. Different partitions can be placed on different nodes in a...

IntroWhy need multiple machines Scalability → If your data volume, read load, or write load grows bigger than a single m...

CompatibilityMorden software development will use rolling upgrade or staged rollout, which means deploying the new version to...

OLTP & OLAPOLTP → Online Transaction Processing. OLAP → Online Analytics Processing. A transaction needn’t have...

LogHere, we define log as an append-only sequence of records. IndexIndex is an additional data structure, which doesn’t affe...

Data ModelA data model is an abstract model that organizes elements of data and standardizes how they relate to one another a...

IntroCPU is no longer the bottle neck. New problems are amount of data, complexity of data and the speed of changing. We call...