Sequential Scans

Sequential Scans in QueryWise's Query Insights provide detailed information about your database operations. The information is presented in the following columns:

• Table: This column displays the name of the table in your PostgreSQL database.
• n_live_tup: In PostgreSQL, this column shows the number of live tuples in the table. Live tuples are the rows in a table that are not marked for deletion.
• seq_scan: This column indicates the number of sequential scans performed on the table in PostgreSQL. Sequential scans involve scanning the entire table to retrieve the desired data.
• seq_tup_read: This column shows the number of sequential tuples read from the table in PostgreSQL. This can be a useful metric for understanding the volume of data being processed in your queries.
• write_activity: This column displays the write activity on the table in PostgreSQL. High write activity may indicate a high rate of data insertion or update operations.
• index_count: This column indicates the number of indexes on the table in PostgreSQL. Indexes can improve query performance by allowing the database to quickly locate the data without having to scan the entire table.
• index Tuple Fetch: In PostgreSQL, this column shows the number of index tuples fetched from the table. This can be a useful metric for understanding the efficiency of your index usage.

Understanding these metrics can help you optimize your database operations and improve the performance of your queries.

Sequential scans are a fundamental operation in database systems. They involve scanning the entire table to retrieve the desired data. While this may seem inefficient, sequential scans can be faster than index scans for larger tables or when a significant portion of the table's data is required. By monitoring the number and performance of sequential scans, you can identify potential bottlenecks and areas for optimization in your database. This can lead to improved query performance and overall database efficiency.