150 Snowflake Interview Questions and Answers for Freshers in 2025
Looking to land your first job in data engineering or cloud data warehousing? Then the 150 Snowflake Interview Questions and Answers for Freshers in 2025 is exactly what you need. This comprehensive collection is carefully compiled based on real interview experiences and frequently asked questions from top MNCs like TCS, Infosys, Wipro, Cognizant, Capgemini, and Accenture. These companies often assess candidates on their practical understanding of Snowflake, not just theoretical knowledge, and this curated list prepares you precisely for that.
Each question is handpicked to reflect the most relevant topics in the current job market—covering Snowflake architecture, performance tuning, SQL queries, virtual warehouses, data sharing, time travel, fail-safe, and more. The answers are explained in simple, beginner-friendly language, making it perfect for freshers who are still learning the ropes. It also includes scenario-based questions and best-practice approaches to help you think like a problem-solver—exactly what top tech employers are looking for.
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150 Snowflake Interview Questions and Answers for Freshers in 2025- collected from TOP MNC Companies
- What is Snowflake?
Snowflake is a cloud-based data warehousing platform that allows you to store and analyze data. It supports structured and semi-structured data. It’s built to work on AWS, Azure, and Google Cloud.
- What makes Snowflake different from traditional data warehouses?
Snowflake separates compute and storage, so you can scale them independently. It’s cloud-native, offers automatic scaling, and supports SQL natively. This architecture increases flexibility and performance.
- What is virtual warehouse in Snowflake?
A virtual warehouse provides compute resources to execute SQL queries. It consists of CPU, memory, and temporary storage. It can be scaled up or down without affecting data.
- What are the key features of Snowflake?
Snowflake offers auto-scaling, multi-cluster warehouses, data sharing, and zero-copy cloning. It supports semi-structured data and separates storage from compute. It also ensures automatic tuning and maintenance.
- What is Time Travel in Snowflake?
Time Travel allows you to access historical data that has been changed or deleted. You can query data as it existed at a specific time in the past. It helps in recovering from accidental changes.
- What is Fail-safe in Snowflake?
Fail-safe provides a 7-day period to recover historical data after Time Travel ends. It is used for disaster recovery by Snowflake support team. Users can’t directly access it.
- What is a schema in Snowflake?
A schema is a logical container for database objects like tables, views, and procedures. It organizes data within a database. You can have multiple schemas in one database.
- What types of data does Snowflake support?
Snowflake supports structured (tables), semi-structured (JSON, XML, Parquet), and unstructured data. It can automatically parse and store semi-structured formats. It stores all data in a columnar format.
- What is Snowflake’s architecture?
Snowflake uses a hybrid architecture with three layers: database storage, compute (virtual warehouses), and cloud services. This separation provides scalability and concurrency. It’s built for cloud platforms only.
- What is a stage in Snowflake?
A stage is a location for uploading data files before loading into tables. It can be internal (within Snowflake) or external (e.g., AWS S3). Staged data is accessed using SQL commands.
- How do you load data into Snowflake?
Data is loaded using the COPY INTO command from stages. Files can be in CSV, JSON, or other supported formats. You can use SnowSQL or the Web UI to manage loading.
- What is SnowSQL?
SnowSQL is a command-line tool provided by Snowflake to connect and interact with your Snowflake account. You can run SQL commands and scripts using it. It’s useful for data loading and automation.
- What are file formats in Snowflake?
File formats define how Snowflake reads files during loading. Formats include CSV, JSON, AVRO, PARQUET, and more. You must specify file format options while loading data.
- What is the difference between internal and external stages?
Internal stages are managed within Snowflake and store files in Snowflake-managed locations. External stages use cloud storage like AWS S3 or Azure Blob. Internal stages are easier for beginners.
- What is clustering in Snowflake?
Clustering improves performance by organizing data in a specified order. It helps with faster query processing for large datasets. You define clustering keys on large tables.
- What is auto-suspend in Snowflake?
Auto-suspend automatically pauses a virtual warehouse after a period of inactivity. It helps save compute costs. Warehouses resume when a query is run again.
- What is auto-resume in Snowflake?
Auto-resume restarts a warehouse when a query is submitted after suspension. It ensures operations are not blocked due to inactive compute. Combined with auto-suspend, it optimizes cost and performance.
- What is a Snowflake share?
A share is a way to share data between Snowflake accounts without copying it. Providers can give access to consumers using secure data sharing. It helps collaborate across organizations easily.
- What is caching in Snowflake?
Snowflake caches query results, metadata, and data in memory for faster performance. There are three levels: result cache, metadata cache, and disk cache. Caching reduces query response time.
- What is semi-structured data in Snowflake?
Semi-structured data includes JSON, XML, AVRO, and PARQUET. Snowflake automatically parses and flattens these formats. You can use SQL queries to extract and transform data easily.
- What is VARIANT data type?
VARIANT is a flexible data type that can store semi-structured data like JSON. It maintains the original format and allows easy querying. It’s commonly used for dynamic fields.
- What is COPY INTO command?
COPY INTO is used to load data from a stage into a Snowflake table. It defines source, destination, file format, and load options. It’s the main command for data ingestion.
- How do you monitor query performance in Snowflake?
You can use the Query History view in the Snowflake UI or SQL commands. It shows execution time, warehouse used, and query steps. Monitoring helps optimize long-running queries.
- What is result cache?
Result cache stores the results of previously executed queries. If the same query runs again, results are returned instantly. It reduces compute usage and improves speed.
- What are roles in Snowflake?
Roles manage user access and permissions. You assign roles to users and roles are granted privileges on objects. It follows a role-based access control (RBAC) model.
- What is a warehouse size in Snowflake?
Warehouse size determines the compute power, such as X-Small, Small, Medium, etc. Larger sizes run queries faster but cost more. You can change the size anytime.
- What happens when two users run the same query in Snowflake?
If the data hasn’t changed, Snowflake uses the result cache for both users. It returns results instantly without re-computing. This ensures efficiency and concurrency.
- What is zero-copy cloning in Snowflake?
Zero-copy cloning creates a copy of a table, schema, or database without duplicating data. It uses metadata pointers, saving time and space. You can test changes safely on clones.
- What is a task in Snowflake?
A task is a scheduled SQL job that runs automatically. It can refresh data, transform tables, or trigger pipelines. Tasks are managed using SQL syntax.
- How do you secure data in Snowflake?
Snowflake secures data with encryption at rest and in transit. It also uses access control, masking, and network policies. You can enforce strict roles and privileges.
- What is metadata in Snowflake?
Metadata is data about your data, like table names, columns, sizes, and timestamps. Snowflake stores metadata separately and updates it automatically. You can access it using SQL queries or the UI.
- What is INFORMATION_SCHEMA in Snowflake?
INFORMATION_SCHEMA is a system-defined schema that stores metadata. It includes tables like TABLES, COLUMNS, and VIEWS to inspect your database structure. It’s helpful for auditing and documentation.
- Can Snowflake connect to BI tools?
Yes, Snowflake integrates easily with BI tools like Tableau, Power BI, and Looker. You use ODBC, JDBC, or connectors for integration. These tools help visualize and analyze your data.
- What is a sequence in Snowflake?
A sequence generates unique numeric values automatically. It’s often used for primary keys or unique identifiers. You can increment and reset it as needed.
- What is multi-cluster warehouse in Snowflake?
A multi-cluster warehouse allows multiple compute clusters to process queries simultaneously. It improves performance during high concurrency. It can scale automatically based on load.
- What is lateral flatten in Snowflake?
LATERAL FLATTEN is used to convert semi-structured data into rows. It helps to extract values from nested arrays like in JSON. It’s useful when working with complex data.
- What is a view in Snowflake?
A view is a saved SQL query that behaves like a table. It shows real-time results based on underlying data. Views can be secure or regular.
- What is a secure view?
A secure view hides the logic of the query and restricts metadata access. It’s useful when sharing data externally. It ensures privacy and data protection.
- What are masking policies in Snowflake?
Masking policies hide or obfuscate sensitive data based on user roles. You can define rules using SQL functions. They are applied dynamically during query execution.
- What are materialized views?
Materialized views store precomputed results of a query. They improve performance for repetitive queries. However, they require maintenance and storage space.
- What is data sharing in Snowflake?
Data sharing allows you to share data with another Snowflake account without copying. It’s real-time and secure. Recipients can query shared data instantly.
- What is Snowflake Marketplace?
Snowflake Marketplace is a platform where providers share live, ready-to-query datasets. Users can find public or commercial datasets easily. It helps with external data integration.
- What is the difference between permanent, transient, and temporary tables?
Permanent tables store data long-term with fail-safe. Transient tables are for short-term use without fail-safe. Temporary tables exist only in a session.
- What is session in Snowflake?
A session is the period between login and logout of a user. Temporary tables and session variables exist only during the session. It ends when you disconnect.
- How do you delete a table in Snowflake?
Use the SQL command DROP TABLE table_name. It removes the table and its data. You can recover it using Time Travel if within retention period.
- How to check storage usage in Snowflake?
You can check storage using Account Usage views or UI dashboards. It shows daily usage per database or table. It helps with cost monitoring.
- What is COPY INTO <location> used for?
This command exports data from Snowflake tables to files in a stage. It’s useful for backups or sharing data externally. You can define format and compression.
- What is clustering key in Snowflake?
A clustering key defines how rows are physically ordered. It helps optimize large table queries. It’s useful for range filtering and sorting performance.
- What is a pipe in Snowflake?
A pipe defines a continuous data loading process using Snowpipe. It automates ingestion from stages into tables. It’s triggered by file arrival.
- What is Snowpipe?
Snowpipe is a continuous data ingestion service. It loads data automatically from stages to tables as soon as it arrives. It supports auto-ingest from cloud storage.
- How do you monitor Snowpipe?
You can monitor Snowpipe using the LOAD_HISTORY function or UI. It shows file status, load time, and errors. Alerts can also be set up via events.
- What are warehouses billed on in Snowflake?
Warehouses are billed based on compute usage in credits per second. Billing starts when the warehouse is running. Auto-suspend helps control costs.
- How is data stored in Snowflake?
Data is stored in micro-partitions in a columnar format. Snowflake compresses and encrypts data automatically. Partitions are optimized for performance.
- What is a stream in Snowflake?
A stream tracks changes (inserts, updates, deletes) to a table. It enables change data capture for downstream processing. You use it with tasks or pipelines.
- What is an external function?
An external function allows calling external APIs from Snowflake SQL. It uses secure connections to access services outside Snowflake. Useful for enrichment or ML tasks.
- What is a stored procedure in Snowflake?
A stored procedure contains SQL statements wrapped in a program logic. You can use loops, conditions, and variables. It helps automate data workflows.
- What is a user-defined function (UDF)?
A UDF allows you to create custom logic using SQL or JavaScript. It works like built-in functions. It’s reusable and simplifies complex calculations.
- What is a role hierarchy in Snowflake?
Roles can inherit privileges from other roles, forming a hierarchy. This simplifies access control. For example, a manager role can inherit user role privileges.
- What is the default retention period for Time Travel?
For permanent tables, the default retention is 1 day. You can increase it up to 90 days. Transient and temporary tables have limited or no Time Travel.
- What is a masking policy and how do you apply it?
A masking policy hides sensitive data like phone numbers or emails based on roles. You define it using SQL and apply it to columns. It activates during query time.
- How does Snowflake handle concurrency?
Snowflake handles concurrency by separating compute clusters for each workload. Multi-cluster warehouses automatically scale to support many users. This avoids resource contention and maintains fast query performance.
- What is the role of Cloud Services layer in Snowflake?
The Cloud Services layer manages authentication, metadata, infrastructure management, and query optimization. It orchestrates all activities between storage and compute layers. This layer ensures seamless user experience.
- Can Snowflake work with unstructured data?
Snowflake primarily supports structured and semi-structured data, but unstructured data can be stored as external files. You manage unstructured data externally in cloud storage and query metadata within Snowflake.
- What is a multi-table insert in Snowflake?
Multi-table insert lets you insert data into multiple tables using a single SQL command. It helps avoid multiple insert statements and improves performance. It’s useful for data transformation workflows.
- What is the difference between a schema and a database?
A database is a container for schemas, and schemas contain tables and other objects. Databases are higher-level containers. This hierarchy helps organize large datasets logically.
- How does Snowflake optimize query performance?
Snowflake uses automatic clustering, pruning, and caching to optimize queries. Its query optimizer chooses efficient execution plans. Separation of compute and storage allows dynamic resource allocation.
- What are micro-partitions?
Micro-partitions are immutable contiguous units of storage that hold compressed columnar data. They allow fast pruning during queries. Snowflake manages micro-partitioning automatically.
- What is data pruning in Snowflake?
Data pruning skips scanning irrelevant micro-partitions based on query filters. It speeds up query execution by reducing data scanned. This optimization happens transparently.
- How do you unload data from Snowflake?
Use the COPY INTO command to export table data to an external stage or cloud storage. You can specify file format and compression. This supports data sharing and backups.
- What are Snowflake tasks used for?
Tasks automate SQL statements on a schedule or based on event triggers. They help with periodic data transformations and pipeline orchestration. Tasks improve workflow automation.
- How does Snowflake encrypt data?
Snowflake encrypts data at rest and in transit using AES 256-bit encryption. Keys are managed automatically or by customers using BYOK. Encryption ensures data security compliance.
- What is BYOK in Snowflake?
Bring Your Own Key (BYOK) lets customers control encryption keys externally. It enhances data security and control. Snowflake integrates with cloud key management systems.
- How do you grant privileges in Snowflake?
Privileges are granted to roles using GRANT statements on objects like tables, schemas, or databases. Users get access by assigning roles. This supports fine-grained access control.
- What is a secure data share?
A secure data share ensures shared data remains encrypted and protected. It provides governed access without copying data. Secure sharing enforces access policies.
- What is the use of INFORMATION_SCHEMA.TABLES?
This view lists all tables in a database schema, including metadata like creation date and type. It helps administrators and developers inspect database objects. Useful for audits and automation.
- What is an account in Snowflake?
An account is the top-level container for all Snowflake objects owned by a customer. It includes databases, warehouses, users, and roles. Each account is isolated and secure.
- What is data masking?
Data masking hides sensitive information by replacing or obfuscating values. It’s dynamic and role-based in Snowflake. Masking protects privacy during data access.
- What is the difference between a transient table and a temporary table?
Transient tables persist until explicitly dropped but lack fail-safe. Temporary tables exist only for the session duration. Both are useful for different data lifecycles.
- How do you resize a warehouse in Snowflake?
You can change warehouse size dynamically using ALTER WAREHOUSE commands or UI. This adjusts compute resources to meet workload demands. Resizing affects performance and cost.
- How does Snowflake ensure high availability?
Snowflake uses cloud provider infrastructure with replication across regions. It has automatic failover and data redundancy. This ensures continuous access without downtime.
- What is a resource monitor in Snowflake?
A resource monitor tracks and limits credit usage for warehouses. It helps control costs by setting thresholds and alerts. You can suspend warehouses when limits are reached.
- What is continuous data ingestion?
Continuous data ingestion automatically loads data in near real-time. Snowpipe is Snowflake’s service for this. It simplifies pipelines by avoiding manual batch loads.
- Can Snowflake support JSON data?
Yes, JSON is supported as semi-structured data stored in VARIANT columns. Snowflake parses and allows querying JSON fields using SQL. This enables flexible schema designs.
- What is a secure UDF?
A secure user-defined function hides its implementation details and restricts metadata exposure. It protects proprietary logic when sharing functions. Secure UDFs enhance security.
- How do you use COPY INTO command for bulk loading?
COPY INTO copies data files from a stage into a table efficiently. It supports parallel processing and error handling. It’s the standard method for large data ingestion.
- What is the difference between internal and external tables?
Internal tables store data within Snowflake’s managed storage. External tables reference data stored externally in cloud storage. External tables allow querying external data without loading.
- What is an external table in Snowflake?
An external table is a table object that points to data stored outside Snowflake, like in S3. It allows querying external files using SQL. Useful for data lake integration.
- What is the use of GET_DDL function?
GET_DDL returns the DDL statements that create a specified object. It helps in object cloning, migration, and documentation. It’s useful for backup and auditing.
- What is an integration in Snowflake?
An integration configures Snowflake to communicate securely with external services like cloud storage or OAuth providers. It simplifies external connectivity. Examples include AWS S3 or Azure Blob integrations.
- How do you manage user authentication in Snowflake?
Snowflake supports username/password, SSO, OAuth, and multi-factor authentication. It integrates with identity providers for secure access. Authentication controls user access and security.
- What is the Snowflake Time Travel feature?
Time Travel lets you access historical data versions up to a set retention period. It helps recover deleted or modified data easily. You can query or restore tables to a previous state.
- What is Fail-safe in Snowflake?
Fail-safe is a 7-day data recovery period after Time Travel expires. It’s for emergency data restoration by Snowflake support only. Fail-safe is not user-accessible.
- What are micro-partitions metadata?
Metadata stores details about micro-partitions like min/max column values. It enables pruning to optimize queries. This metadata is automatically maintained by Snowflake.
- How is data compressed in Snowflake?
Snowflake uses columnar compression techniques automatically. It reduces storage costs and improves query speed. Compression is transparent to users.
- Can you explain Snowflake’s zero-copy cloning?
Zero-copy cloning creates a full copy of database objects instantly without data duplication. It uses pointers to original data. This saves time and storage.
- What is the difference between a warehouse and a database in Snowflake?
A warehouse provides compute resources for query execution. A database stores data objects like tables and schemas. Both are separate components.
- How do you use Snowflake with Python?
You can connect Snowflake with Python using the Snowflake Connector library. It allows executing SQL queries programmatically. Useful for automation and data pipelines.
- What is Snowflake’s multi-cluster warehouse?
It allows scaling compute clusters automatically for concurrent workloads. Improves performance during peak times. Reduces query queuing.
- What is the use of Streams in Snowflake?
Streams track data changes in tables for incremental processing. Useful in ETL pipelines for CDC. Supports efficient data synchronization.
- How do you create a user in Snowflake?
Use the CREATE USER SQL command with attributes like password and role. Users gain access based on assigned roles. User creation is controlled by admin roles.
- What is the maximum size of a Snowflake table?
Snowflake tables have no hard size limit. They can scale to petabytes depending on storage. Performance depends on warehouse size and partitioning.
- What is the function of the virtual warehouse?
A virtual warehouse handles query processing by providing compute resources. Multiple warehouses can run independently. Size and number affect speed and cost.
- How is Snowflake different from traditional databases?
Snowflake separates compute and storage, allowing independent scaling. It’s fully managed and cloud-native. Supports semi-structured data natively.
- What is the difference between VARIANT and OBJECT data types?
VARIANT stores semi-structured data like JSON or XML. OBJECT stores key-value pairs with fixed structure. Both allow flexible data modeling.
- How does Snowflake ensure data security?
Snowflake uses encryption, access controls, and network security. Supports multi-factor authentication and role-based access. Compliance certifications add trust.
- What is the purpose of a role in Snowflake?
Roles control user permissions and access to objects. They simplify privilege management. Users inherit permissions by assigned roles.
- Can Snowflake support real-time analytics?
Yes, Snowflake supports real-time analytics via Snowpipe and continuous data ingestion. Queries run on fresh data with minimal latency. Suitable for near real-time dashboards.
- What is the use of the INFORMATION_SCHEMA.COLUMNS view?
It provides metadata about columns in tables and views. Includes data type, default values, and nullability. Useful for schema inspection and automation.
- How does Snowflake handle backup and restore?
Snowflake’s Time Travel and Fail-safe features enable easy backup and restore. Data snapshots are automatically kept for a retention period. No manual backups required.
- What is the difference between a table and a view?
Tables store actual data physically. Views are saved queries that provide dynamic results. Views don’t store data but reflect underlying table changes.
- How do you optimize query performance in Snowflake?
Use clustering keys, pruning, result caching, and proper warehouse sizing. Avoid large full scans by filtering data. Monitor query profiles for bottlenecks.
- What is the use of the TASKS feature?
Tasks automate SQL executions on a schedule or after dependencies. Useful for ETL jobs and maintenance. Reduces manual intervention.
- How do you grant privileges to roles?
Use the GRANT command specifying the privilege, object, and role. Roles can be nested for inheritance. Ensures secure and manageable access.
- Can Snowflake handle geospatial data?
Yes, Snowflake supports geospatial data types and functions. Useful for location-based queries. Enables spatial analytics within SQL.
- What is a masking policy?
Masking policies protect sensitive data by dynamically hiding or altering it based on roles. Applied at query time. Ensures compliance with data privacy rules.
- How does Snowflake handle semi-structured data?
Snowflake stores semi-structured data in VARIANT columns. It allows querying nested data with SQL functions. Supports JSON, XML, AVRO, Parquet, etc.
- What is the difference between internal and external stages?
Internal stages store files inside Snowflake’s managed storage. External stages reference files in cloud storage like S3. Both used for loading/unloading data.
- How do you monitor resource usage in Snowflake?
Use ACCOUNT_USAGE views, QUERY_HISTORY, and Resource Monitors. These provide insights into credits, queries, and warehouses. Helps control cost and performance.
- What is the difference between COPY INTO TABLE and COPY INTO LOCATION?
COPY INTO TABLE loads data from a stage into a Snowflake table. COPY INTO LOCATION exports table data to an external stage or cloud storage. Both are data transfer commands.
- How can Snowflake integrate with other cloud services?
Snowflake integrates with AWS, Azure, and GCP services via connectors and APIs. It supports data ingestion, sharing, and analytics with external tools. This enables hybrid cloud architectures.
- What is Snowpipe in Snowflake?
Snowpipe is a continuous data ingestion service that loads data automatically as soon as it arrives in cloud storage. It eliminates manual batch loading and reduces latency. Snowpipe supports near real-time data processing.
- How do you create a secure view?
A secure view hides the underlying data’s details and restricts metadata exposure. Use the SECURE keyword when creating the view. It ensures sensitive data is protected from unauthorized users.
- What is a multi-cluster warehouse in Snowflake?
It allows multiple compute clusters to run simultaneously under one warehouse. This helps handle concurrent workloads efficiently. It scales automatically based on demand.
- Can Snowflake run stored procedures?
Yes, Snowflake supports stored procedures written in SQL or JavaScript. They encapsulate business logic for reuse. Stored procedures simplify complex operations.
- What are Snowflake tasks used for?
Tasks automate the execution of SQL statements on a schedule or based on events. Useful for running ETL jobs and maintenance. They help build automated data pipelines.
- What is the difference between transient and permanent tables?
Transient tables have no Fail-safe and are cheaper but less durable. Permanent tables have Fail-safe and Time Travel for data recovery. Choice depends on data retention needs.
- How do you manage roles and privileges in Snowflake?
Roles define access permissions and can be granted to users. Privileges are assigned to roles for objects like tables and schemas. This hierarchical system ensures secure access control.
- What is the difference between a user and a role?
Users are individual accounts that log into Snowflake. Roles are collections of privileges assigned to users. Roles simplify permission management.
- How do you load data from S3 to Snowflake?
Use the COPY INTO command with an external stage pointing to the S3 bucket. Files are loaded into tables efficiently. Snowflake manages data parsing and compression.
- What is the maximum size of a Snowflake warehouse?
Warehouses can scale up to X-Large or even larger depending on the edition. Size determines the compute resources available for query processing. Larger warehouses handle heavier workloads.
- What is a stream in Snowflake?
A stream tracks changes (inserts, updates, deletes) in a table for incremental processing. It supports Change Data Capture (CDC). Streams enable efficient ETL workflows.
- How does Snowflake support JSON queries?
JSON data stored in VARIANT columns can be queried using dot notation and functions. Snowflake parses and extracts nested JSON elements easily. This supports semi-structured data analytics.
- What is data clustering in Snowflake?
Clustering organizes data within micro-partitions based on selected columns. It improves query performance by reducing scanned data. Snowflake can automatically recluster tables.
- How do you handle duplicate data in Snowflake?
You can remove duplicates using SQL DISTINCT or ROW_NUMBER with filtering. Streams also help detect changes and duplicates during ingestion. Data quality depends on ingestion logic.
- What is the difference between a view and a materialized view?
Views are virtual and run queries at execution time. Materialized views store query results physically for faster access. Materialized views require maintenance to stay updated.
- How does Snowflake handle schema evolution?
Snowflake allows adding or dropping columns without downtime. It supports semi-structured data changes flexibly. Schema changes are easy to apply.
- What is a Snowflake stage?
A stage is a location to store data files before loading or after unloading. Stages can be internal or external (cloud storage). They simplify data ingestion workflows.
- What is the function of the RESULT_SCAN function?
RESULT_SCAN lets you query results of a previous query by its query ID. It avoids re-running expensive queries. Useful for debugging and analysis.
- How does Snowflake charge for usage?
Charges are based on storage used and compute credits consumed by warehouses. Compute costs depend on warehouse size and runtime. Efficient resource use controls costs.
- What is data sharing in Snowflake?
Data sharing allows direct, secure access to data across Snowflake accounts without copying. It enables collaboration and data monetization. Shared data remains in the provider’s account.
- How do you optimize storage costs in Snowflake?
Use data retention policies, remove unused tables, and compress data effectively. Use transient tables where possible. Monitor storage usage regularly.
- What is the difference between bulk loading and continuous loading?
Bulk loading involves loading large datasets in batches using COPY commands. Continuous loading uses Snowpipe for near real-time ingestion. Both serve different pipeline needs.
- How do you revoke privileges in Snowflake?
Use the REVOKE command specifying the privilege, object, and role. It removes access rights immediately. Helps maintain secure environments.
- What is the use of the ACCOUNT_USAGE schema?
ACCOUNT_USAGE provides metadata and usage data views for monitoring Snowflake activity. Includes info on queries, warehouses, and users. Essential for auditing and cost management.
- Can Snowflake integrate with BI tools?
Yes, Snowflake supports connectors and drivers for tools like Tableau, Power BI, and Looker. It enables seamless analytics and reporting. Integration supports live querying.
- How do you handle error handling in Snowflake?
Snowflake supports TRY-CATCH in stored procedures and error codes in query results. Logging and alerting can be automated. Proper error handling improves reliability.
- What is the use of the SYSTEM$CLUSTERING_INFORMATION function?
It provides details about clustering keys and their effectiveness on a table. Helps tune clustering strategies. Improves query performance.
- How is data lineage managed in Snowflake?
Data lineage tracks data flow from sources through transformations to targets. Snowflake logs metadata changes, supporting lineage tools integration. Important for governance.
- How do you connect Snowflake with Spark?
Use Snowflake Spark Connector to read/write data between Spark and Snowflake. Enables big data processing and analytics. Supports efficient data exchange.
- What is the role of metadata in Snowflake?
Metadata stores information about data structure, location, and access. It enables query optimization, security, and data management. Snowflake manages metadata automatically.
