DataViz Migration - an upstream/downstream SQL interoperability layer - {oa-lake}

Decision-support platforms often rely on several databases, several data warehouses / data lakes, and several reporting tools.
{oa-lake} introduces an intermediate SQL layer between data sources and dataviz tools.
Business rules, business objects, dimensions, measures, and calculations are centralized in this layer and then exposed to consuming tools.
Key point: data sources and reporting tools become independent of one another.
Architecture
{oa-lake} connects simultaneously to multiple data systems: relational databases, data warehouses, lakehouses, files, or APIs.
Queries are federated by a distributed SQL engine that performs the necessary joins, calculations, and transformations.
The resulting SQL remains standard and executable across different engines, which limits technology lock-in.
Business objects are defined once and then exposed to consuming tools.
Data sources
The data stays in its original systems.
Oracle, SQL Server, PostgreSQL, DB2, BigQuery, Snowflake, Redshift, Azure SQL (and others), or files can be queried within a single request.
The SQL Push-Down mechanism avoids any systematic copying of data: queries run directly against the existing systems, respecting the architectures already in place.
Typical use case: build a dashboard from data spread across several platforms with no prior migration.
SQL business layer
Dimensions, measures, hierarchies, and calculation rules are centralized in {oa-lake}.
This layer becomes the single entry point for reporting tools.
Business rules are no longer duplicated across every dataviz platform.
Key point: a single definition of indicators for the entire decision-support system.
Parquet cache
Data can be materialized in Parquet format.
This caching layer reduces response times and limits load on source systems. It’s managed automatically based on observed usage, with no manual intervention.
Typical use case: speed up the most expensive analytical processing.
Data visualization
Reporting tools connect to the model exposed by {oa-lake}.
Power BI, Looker, Spotfire, Tableau, Qlik, SAP BusinessObjects, or any SQL-compatible tool can use the same business objects.
Switching dataviz tools no longer requires rebuilding dimensions, measures, and calculation rules.
Progressive migration
Several tools can coexist during a transition phase.
The same business model can be exposed simultaneously to several reporting platforms.
Result: progressive migration of usage with no change to the data systems.
Data Lineage
The data lineage reconstructed by {openAudit} remains available across the whole chain.
Dependencies are documented from the source systems all the way to the indicators exposed in the dashboards.
Key point: transformations, calculations, and usage remain traceable across the entire architecture.