Indicates the user preference as to when schemas should be generated and saved.
Possible ValuesNever, OnUse, OnStart, OnCreate
Available settings are the following:
- Never: A schema file will never be generated.
- OnUse: A schema file will be generated the first time a table is referenced, provided the schema file for the table does not already exist.
- OnStart: A schema file will be generated at connection time for any tables that do not currently have a schema file.
- OnCreate: A schema file will be generated by when running a CREATE TABLE SQL query.
Generate Schemas with SQL
When you set GenerateSchemaFiles to OnUse, the connector generates schemas as you execute SELECT queries. Schemas are generated for each table referenced in the query.
When you set GenerateSchemaFiles to OnCreate, schemas are only generated when a CREATE TABLE query is executed.
Generate Schemas on Connection
Another way to use this property is to obtain schemas for every table in your database when you connect. To do so, set GenerateSchemaFiles to OnStart and connect.
Alternatives to Static Schemas
If your data structures are volatile, consider setting GenerateSchemaFiles to Never and using dynamic schemas. See Automatic Schema Discovery for more information about dynamic schemas.
Schema files have a simple format that makes them easy to modify. See Custom Schema Definitions for more information.