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Known Issues and Limitations
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Known Issues and Limitations

In this article
  • Known Issues and Limitations
  • Automation
  • Output Display
  • Data Type Incompatibility
  • Script Execution via GraphQL Query
  • Working with SQL
  • Business Intelligence
  • Handling of Empty Values in Tables

This page describes known limitations in the Operavix system by module:

Automation

Output Display

If table columns have identical names before the dot (e.g., col.id, col.employee), these columns will appear as nested in script output (col: id, employee).

Data Type Incompatibility

The Int64 and UInt64 data types are incompatible. During script execution, errors may occur when transferring data between columns of these types.

Script Execution via GraphQL Query

Only scripts with the Manual start trigger can be executed via GraphQL. Scripts with the Scheduler trigger cannot be executed this way — they can only be enabled or disabled, but not run once via a query.

Working with SQL

  • Operavix does not support working with SQL procedures
  • Each automation block that interacts with databases is designed to execute only one SQL query. If multiple sequential queries are required, add a separate block for each query in the script

Business Intelligence

Handling of Empty Values in Tables

Created and imported tables are stored on user ClickHouse servers. For each value, a field with the corresponding data type is created. For each field with the Nullable property, two fields are created in the database.

ClickHouse uses the following for storing Nullable fields:

  • A separate file with NULL masks. The mask determines whether a cell contains NULL or a value
  • A file with values

If the mask indicates that a cell contains NULL, the values file stores the default value for the data type. For example, if the field is of type Nullable(Int8), the cell will store the default value for Int8. This behavior increases storage size.

Warning

When designing databases, note that using fields with the Nullable property reduces performance and may cause system errors—e.g., incorrect widget rendering in dashboards. To resolve this, uncheck the Nullable option next to the column’s data type in the Data Model.

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