MySQL Collected Data

This page describes what Sifflet imports from your MySQL database once the MySQL source is connected.

Imported Assets

Sifflet imports the following objects from the database configured in the source:

• Tables
• Views

Collected Metadata

Sifflet reads metadata from INFORMATION_SCHEMA. For each table and view, Sifflet collects:

• Name and database
• Description (the table comment)
• Columns: name, data type, nullability, default value, size, and description (the column comment)

The Freshness (Update Time Gap) monitor reads the last update time of a table from INFORMATION_SCHEMA.TABLES (UPDATE_TIME, or CREATE_TIME when no update time is available). MySQL doesn't keep UPDATE_TIME for every storage engine and doesn't persist it across server restarts for InnoDB tables: see the MySQL documentation.

Lineage

Sifflet doesn't extract lineage between tables inside MySQL (from query logs or view definitions).

MySQL tables appear in lineage when other integrations reference them, for example BI tools, dbt, or data pipelines. Sifflet links these assets when the host, port, and database configured in the other tool match the MySQL source.

Data Freshness

Sifflet refreshes the MySQL metadata on the source schedule. See Integrations Management for the default frequency and scheduling options.

In MySQL 8.0 and later, INFORMATION_SCHEMA.TABLES serves cached values for UPDATE_TIME, refreshed according to the information_schema_stats_expiry system variable (24 hours by default). The Freshness (Update Time Gap) monitor can only detect updates as recent as this cache.

Data Exposure

Sifflet stores metadata and monitor results. Some features read and display row-level data from your tables: data preview and the failing rows of monitors. See Security for details on the data that Sifflet accesses and stores.