DEA-C02: SnowPro Advanced — Data Engineer

Snowflake's SYSTEM$CLUSTERING_DEPTH can calculate average clustering depth for any specified parenthesized set of table columns, and a lower depth indicates better clustering for that set. Evaluating (client_id, warehouse, product_id) and (client_id, destination_city, product_id) provides the needed comparison of valid candidate keys that each include client_id plus two application access columns. SYSTEM$CLUSTERING_INFORMATION('shipments', 3) returns clustering errors, not clustering information for a proposed column combination.

ESCAPE_UNENCLOSED_FIELD specifies the escape character for unenclosed field values during data unloading. Snowflake recognizes \\ as the common escape sequence for a literal backslash, so the option value must be '\\'.

A pre-signed URL provides direct temporary access to a staged file without Snowflake authentication, and its expiration_time can be set to 3,600 seconds (60 minutes). SYSTEM$SEND_EMAIL can send the email containing that link. Scoped URLs instead follow the persisted query-results period, currently 24 hours, while stage file URLs require stage privileges and are not temporary.

Cortex AI SQL usage history supplies per-query usage together with model metadata and a query ID. That query ID can be joined to SNOWFLAKE.ACCOUNT_USAGE.QUERY_HISTORY, which contains the SQL text, while a scheduled task can send a notification when the per-query threshold is exceeded. Warehouse resource monitors and daily metering are aggregate controls, so they cannot identify the individual Cortex query and model. In the current CORTEX_AISQL_USAGE_HISTORY view, the billed-credit column is named TOKEN_CREDITS; implementations should use that current column name. CORTEX_AISQL_USAGE_HISTORY view, QUERY_HISTORY view

For a high-cardinality column, define the clustering key as an order-preserving expression on that column, such as converting a timestamp to a date. The expression reduces the number of distinct key values while retaining useful pruning behavior.