This document discusses importing or reverse-engineering structures into Hackolade data models from various sources. It describes reverse-engineering existing database instances or file-based sources like JSON or YAML to derive a data model. Different techniques are used depending on the source, such as inferring the schema, using connection parameters, or normalizing nested structures. The document provides resources for further reading on reverse-engineering and data modeling.

1. Hackolade Tutorial
Part 8 – Import or reverse-engineer
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2. Reverse-engineering
• Used to import structures into existing/new data models
• For modeling / documenting existing instances
• Starting point for further work:
• Descriptions and constraints
• Schema evolution
• Sharing with business-facing data dictionaries
• Data governance and compliance
• Consistency across different environments and deployments
• Etc…
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3. Sources for reverse-engineering
• JSON or YAML document
• Infer the schema from data files
• JSON schema or YAML schema
• With optional normalization of nested
structures into separate entities
• DDLs from
• Oracle, MS SQL Server, MariaDB, MySQL,
PostgreSQL, Hadoop Hive, Snowflake, Teradata,
DB2, Informix, Redshift
• XSD Schema
• Excel file template
• Target specific instances
• databases, schema files, schema registries,
and cloud storage
• Data dictionaries (eg. Collibra)
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4. Importing file-based sources
• You can select one or more files
• Usually imports will become entities in
the ERD
• But you can import them as definitions /
user-defined types / component schemas
• You can merge into the current model’s
new or existing container
• When importing nested structures into
RDBMS targets, you can normalize
automatically
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5. Reverse-engineering instances
• From on-prem or cloud
instances: connection
parameters required
• Stored on local machine, with
encrypted passwords
• Different process and
parameters for each
technology
• Sometimes using sampling
• Sometimes using inferencing of
schema
• Also available from CLI!
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6. Reading material
• See Hackolade online documentation
• The Hackolade Blog
• This excellent new book:
MongoDB Data Modeling & Schema Design
• Many of the principles in the book are related to query
driven modeling based on access patterns!
• Hackolade’s on social media: LinkedIn page, Twitter page
• Download Hackolade studio for free
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7. Questions?
Answers!
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