Programmer Group

@ Warehouse notes Detailed explanation of data warehouse and data mart: ODS, DW, DWD, DWM, DWS, ADS Project requirements and architecture design of shangsilicon Valley data warehouse Shang Silicon Valley data warehouse: 2 data warehouse layering + dimension modeling Construction of 3 data warehouses in the actual combat of shangsilicon Valley ...

@Warehouse notesDetailed explanation of data warehouse and data mart: ODS, DW, DWD, DWM, DWS, ADSProject requirements and architecture design of shangsilicon Valley digital warehouse practice 1Shang Silicon Valley digital warehouse actual combat 2 digital warehouse layered + dimensional modelingConstruction of 3 digital warehouses in shangsilic ...

1. Method 1.1 general In actual development, we need to write a large number of logic codes, which is bound to involve repeated requirements. For example, for the maximum values of 10 and 20 and the maximum values of 11 and 22, the logic code for comparison needs to be written twice. If the logic code for comparison is put into the method, it ...

Actual combat of e-commerce offline warehouse project (Part 2) E-commerce analysis - core transactions 1, Business requirements Select indicators: order quantity, commodity quantity and payment amount, and analyze these indicators by sales region and commodity type. 2, Business database table structure 1. Relationship between databas ...

1, Introduction to e-commerce business 1.1 e-commerce business process The business process of e-commerce can be illustrated by taking the browsing footprint of an ordinary user as an example. Users click the home page of e-commerce to start browsing. They may find their favorite products through classified query or full-text search. Thes ...

1 data tilt Most tasks are completed quickly, and only one or a few tasks are executed slowly or even fail. This phenomenon is data skew.The data skew is divided into single table query with GroupBy field and two table (or multi table) Join query. 1.1 single table data skew optimization 1.1.1 the map side performs aggregation - GroupBy opera ...