Viewing log messages¶

You can view the log messages either through Snowsight or by querying the event table in which log entries are stored.

Note

Before you can begin using log messages, you must enable telemetry data collection.

View log entries in Snowsight¶

Note

Snowsight support for logging and tracing is a preview feature available to all accounts.

You can use Snowsight to view log data captured in the event table.

Sign in to Snowsight.
In the navigation menu, select Monitoring » Traces and Logs.

In the Traces & Logs page, you can do the following actions:

To filter the displayed rows, use the drop-down menus at the top of the page. You can filter by the following characteristics:
- Date range during which the entry was recorded
- Name of the Snowflake user executing the code that emitted the entry
- Log entry severity
- Programming language of the code that emitted the log entry
To filter entries by a specific time period in the displayed data, select the graph bar representing the time period.
To sort rows, select the name of the column by which you want to sort.

To view more detailed information about an entry in its Details panel, select the entry’s row.

On this panel, you can view more information stored in the event table. The following table describes values in the panel:

Detail	Description
Record Type	Type of event the selected row represents. Retrieved from the RECORD_TYPE column value.
Database	Name of the database containing the code that emitted the entry. Retrieved from the RESOURCE_ATTRIBUTES column `snow.database.name` value.
Schema	Name of the schema containing the code that emitted the entry. Retrieved from the RESOURCE_ATTRIBUTES column `snow.schema.name` value.
Severity	Severity of the log entry. Retrieved from the RECORD column `severity_text` value.
Query ID	ID of the query within which the log entry was emitted. Retrieved from the RESOURCE_ATTRIBUTES column `snow.query.id` value.
Object	Name of the emitted log entry’s source, such as the function or procedure. Retrieved from the RESOURCE_ATTRIBUTES column `snow.executable.name` value.
Warehouse	Name of the warehouse running the query that generated the event. Retrieved from the RESOURCE_ATTRIBUTES column `snow.warehouse.name` value.
Owner	Name of the primary role in the session. Retrieved from the RESOURCE_ATTRIBUTES column `snow.session.role.primary.name` value.
Log Text	Log message text. Retrieved from the VALUE column value.

Query the event table for log entries¶

To access the logged messages, execute the SELECT command on the event table.

An event table has a set of predefined columns that capture information about the logged messages, including the following:

The timestamp when the message was ingested
The scope of the log event, such as the name of the class where the log event was created
The log event source, including the database, schema, user, warehouse
The severity level of the log
The log message

For reference information about the event table’s structure, see Event table columns.

The following sections illustrate with example data how you can query the event table for log message data.

Collected data¶

Output in the following example shows content from a selected subset of columns from an event table after log messages have been captured for two separate handlers: one written in Scala and the other in Python.

For reference information about event table columns that collect log message data, see Data for logs.

---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| TIMESTAMP           | SCOPE                             | RESOURCE_ATTRIBUTES   | RECORD_TYPE | RECORD                       | VALUE                                                      |
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| 2023-04-19 22:00:49 | { "name": "python_logger" }       | **See excerpt below** | LOG         | { "severity_text": "INFO" }  | Logging from Python module.                                |
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| 2023-04-19 22:00:49 | { "name": "python_logger" }       | **See excerpt below** | LOG         | { "severity_text": "INFO" }  | Logging from Python function start.                        |
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| 2023-04-19 22:00:49 | { "name": "python_logger" }       | **See excerpt below** | LOG         | { "severity_text": "ERROR" } | Logging an error from Python handler.                      |
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| 2023-04-19 22:12:55 | { "name": "ScalaLoggingHandler" } | **See excerpt below** | LOG         | { "severity_text": "INFO" }  | Logging from within the Scala constructor.                 |
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| 2023-04-19 22:12:56 | { "name": "ScalaLoggingHandler" } | **See excerpt below** | LOG         | { "severity_text": "INFO" }  | Logging from Scala method start.                           |
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| 2023-04-19 22:12:56 | { "name": "ScalaLoggingHandler" } | **See excerpt below** | LOG         | { "severity_text": "ERROR" } | Logging an error from Scala handler: Something went wrong. |
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

RESOURCE_ATTRIBUTES excerpts¶

The following JSON includes excerpts from values you’d find in the preceding output’s RESOURCE_ATTRIBUTES column. Each snow.executable.name name-value pair is from a different row in the preceding output.

The SELECT query code following this excerpt selects from the RESOURCE_ATTRIBUTES column’s value.

The RESOURCE_ATTRIBUTES column contains data about the event’s source. For reference information, see RESOURCE_ATTRIBUTES column.

{
  ...
  "snow.executable.name": "ADD_TWO_NUMBERS(A FLOAT, B FLOAT):FLOAT"
  ...
}

{
  ...
  "snow.executable.name": "ADD_TWO_NUMBERS(A FLOAT, B FLOAT):FLOAT"
  ...
}

{
  ...
  "snow.executable.name": "ADD_TWO_NUMBERS(A FLOAT, B FLOAT):FLOAT"
  ...
}

{
  ...
  "snow.executable.name": "DO_LOGGING():VARCHAR(16777216)"
  ...
}

{
  ...
  "snow.executable.name": "DO_LOGGING():VARCHAR(16777216)"
  ...
}

{
  ...
  "snow.executable.name": "DO_LOGGING():VARCHAR(16777216)"
  ...
}

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Query with SELECT statement¶

When querying for message data, to select attribute values within a column, use bracket notation, as in the following form:

COLUMN_NAME['attribute_name']

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Code in the following example queries the preceding table with the intention of isolating data related to the Python handler’s log messages. The query selects the severity_text attribute for the log entry severity. It selects the VALUE column’s content for the log message.

The procedure containing the handler is called do_logging. Note that for the query to work, you must specify the procedure name in all capital letters.

SET event_table_name='my_db.public.my_event_table';

SELECT
  TIMESTAMP as time,
  RESOURCE_ATTRIBUTES['snow.executable.name'] as executable,
  RECORD['severity_text'] as severity,
  VALUE as message
FROM
  IDENTIFIER($event_table_name)
WHERE
  SCOPE['name'] = 'python_logger'
  AND RESOURCE_ATTRIBUTES['snow.executable.name'] LIKE '%DO_LOGGING%'
  AND RECORD_TYPE = 'LOG';

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Query results¶

Output in the following example illustrates the query’s result:

----------------------------------------------------------------------------------------------------------------
| TIME                | EXECUTABLE                       | SEVERITY   | MESSAGE                                |
----------------------------------------------------------------------------------------------------------------
| 2023-04-19 22:00:49 | "DO_LOGGING():VARCHAR(16777216)" | "INFO"     | "Logging from Python module."          |
----------------------------------------------------------------------------------------------------------------
| 2023-04-19 22:00:49 | "DO_LOGGING():VARCHAR(16777216)" | "INFO"     | "Logging from Python function start."  |
----------------------------------------------------------------------------------------------------------------
| 2023-04-19 22:00:49 | "DO_LOGGING():VARCHAR(16777216)" | "ERROR"    | "Logging an error from Python handler" |
----------------------------------------------------------------------------------------------------------------