database design - Should a data warehouse ever be a primary data repository? -

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typically data warehouse means consolidate multiple source systems, reporting purposes. there situations idea use data warehouse primary database in own right (i.e. capturing , managing data, not loading system)?

the short answer - no, don't think so. should first designing good, normalized database structure production database - , later worry data warehouse part.

keeping warehouse , production database separate considered "best business practice", perhaps importantly it's design consideration. data warehouse , production database serves 2 different purposes. perhaps important function of production database capture transactions reliably, consistently , unambiguously. matters both when designing database , when choosing software, i.e. database engine.

the design part of shouldn't underestimated - i'd in projects, database design 1 first thing 1 should doing. getting table structure right more important choosing technology.

if you're planning grow, may make sense try , isolate data bit different databases - both because makes easier split database later , run different parts on different hardware (when hit "bleeding edge", it's lot cheaper buy more servers buy more powerful servers) , because may later want split out software modules or reuse them independently of each other. wouldn't want split data warehouse same way.

so recap, start production database, , build data warehouse later - can typically postponed until feel urge combine data different sources or add redundancy production database achieve faster reports.

i working online gambling company 8 years. participated in design of production database, , later responsible building data warehouse - comments above based on of mistakes done , experiences learnt.


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