You have created an external table for Apache Hive partitioned data that resides in a Cloud Storage bucket, which contains a large number of files. You notice that queries against this table are slow You want to improve the performance of these queries What should you do?
Correct Answer: D
BigLake is a Google Cloud service that allows you to query structured data in external data stores such as Cloud Storage, Amazon S3, and Azure Blob Storage with access delegation and governance. BigLake tables extend the capabilities of BigQuery to data lakes and enable a flexible, open lakehouse architecture. By upgrading an external table to a BigLake table, you can improve the performance of your queries by leveraging the BigQuery storage API, which supports data format conversion, predicate pushdown, column projection, and metadata caching. Metadata caching reduces the number of requests to the external data store and speeds up query execution. To upgrade an external table to a BigLake table, you can use the ALTER TABLE statement with the SET OPTIONS clause and specify the enable_metadata_caching option as true. For example: SQL ALTER TABLE hive_partitioned_data SET OPTIONS ( enable_metadata_caching=true ); AI-generated code. Review and use carefully. More info on FAQ. References: * Introduction to BigLake tables * Upgrade an external table to BigLake * BigQuery storage API
Question 212
You have a requirement to insert minute-resolution data from 50,000 sensors into a BigQuery table. You expect significant growth in data volume and need the data to be available within 1 minute of ingestion for real-time analysis of aggregated trends. What should you do?
Correct Answer: D
Question 213
You need to create a near real-time inventory dashboard that reads the main inventory tables in your BigQuery data warehouse. Historical inventory data is stored as inventory balances by item and location. You have several thousand updates to inventory every hour. You want to maximize performance of the dashboard and ensure that the data is accurate. What should you do?
Correct Answer: A
Question 214
You work for a farming company. You have one BigQuery table named sensors, which is about 500 MB and contains the list of your 5000 sensors, with columns for id, name, and location. This table is updated every hour. Each sensor generates one metric every 30 seconds along with a timestamp. which you want to store in BigQuery. You want to run an analytical query on the data once a week for monitoring purposes. You also want to minimize costs. What data model should you use?
Correct Answer: C
For a farming company with a sensor data table updated every 30 seconds, the goal is to minimize costs while facilitating weekly analytical queries. The best data model will effectively manage data storage, update frequency, and query performance. * Partitioned Metrics Table: * Creating a metrics table partitioned by timestamp optimizes query performance and storage costs. * Partitioning by timestamp allows for efficient querying, especially for time-based analyses. * Sensor ID Reference: * Including a sensor_id column in the metrics table that points to the id column in the sensors table ensures data normalization. * This structure avoids redundancy and maintains a clear relationship between sensors and their metrics. * Using INSERT Statements: * Using INSERT statements to append new metrics every 30 seconds is efficient and cost-effective. * INSERT operations are more suitable than UPDATE operations for adding new data entries, especially at high frequencies. * Joining Tables for Analysis: * When running analytical queries, joining the partitioned metrics table with the sensors table as needed provides a comprehensive view of the data. * This approach leverages BigQuery's powerful JOIN capabilities while keeping the data model normalized and efficient. Google Data Engineer References: * BigQuery Partitioned Tables * BigQuery Best Practices * Efficient Data Partitioning * BigQuery Data Modeling Using this data model, the farming company can manage its sensor data effectively, minimize costs, and perform weekly analytical queries with high efficiency.
Question 215
Flowlogistic's CEO wants to gain rapid insight into their customer base so his sales team can be better informed in the field. This team is not very technical, so they've purchased a visualization tool to simplify the creation of BigQuery reports. However, they've been overwhelmed by all the data in the table, and are spending a lot of money on queries trying to find the data they need. You want to solve their problem in the most cost-effective way. What should you do?