Case study · Nordvik Sparebank EN NO

raw.customers

Customer master · approximately 10,000 rows.

One row per customer. Customers are identified by an internal sequential customer_id; the canonical natural key is national_id (Norwegian fødselsnummer). Includes contact details and segment.

Columns

ColumnTypeDescription
customer_idPKBIGINTInternal surrogate, sequential.
national_idTEXT11-digit Norwegian fødselsnummer with MOD-11 check digits.
first_nameTEXTGiven name.
last_nameTEXTFamily name.
emailTEXTEmail address. Nullable.
phoneTEXTMobile or landline. Free-form string.
postal_codeTEXTNorwegian 4-digit postal code.
cityTEXTCity of residence.
segmentTEXTOne of retail, private_banking, student.
onboarded_atTIMESTAMPWhen the customer relationship began.
churned_atTIMESTAMPWhen the customer left. NULL if still active.

Sample rows

customer_idnational_idfirst_namelast_nameemailphonepostal_codecitysegmentonboarded_atchurned_at
114048246173LarsHansenlars.hansen@online.no+47 912345670150Osloretail2019-04-12 00:00:00NULL
227039914802KariOlsenkari.olsen@gmail.com923456785003Bergenprivate_banking2016-09-01 00:00:00NULL
303079853019PerLarsenNULL0047934567897010Trondheimstudent2022-08-22 00:00:00NULL
411128521098AnnePedersenanne.pedersen@hotmail.com+47945678904006Stavangerretail2014-02-19 00:00:002024-11-30 00:00:00
522057740214KnutKarlsenknut.karlsen@icloud.com956789013015Drammenretail2017-06-04 00:00:00NULL

Notes