Parallel query is suitable for the following scenarios:
- Full table scans, index scans, index range scans, index reverse scans, index point queries, and index pushdown.
- Single-table queries, multi-table joins, views, subqueries, and partial CTE queries.
- Multiple JOIN algorithms, including BNL Join, BKA Join, HASH Join, Nested Loop Join, Semi Join, Anti Join, and Outer join.
- Multiple subqueries, including conditional subqueries, scalar subqueries, some correlated subqueries, non-correlated subqueries, and derived tables.
- Multiple data types, including Integer, Character, Floating Point, and Time.
- Arithmetic expressions (+, -, *, %, /, |, and &), conditional expressions (<, <=, >, >=, <>, Between/And, In), logical operations (Or, And, Not), and common functions (Character, Integer, and Time), and aggregation functions (COUNT/SUM/AVG/MIN/MAX)
The count aggregate function can be executed concurrently only when innodb_parallel_select_count is disabled.
- Non-partitioned table queries, and queries for a single partition of partitioned tables
- Order By, Group By/Distinct, Limit/Offset, Where/Having, and Column Projection
- UNION/UNION ALL queries
- EXPLAIN statements to view execution plans. Traditional Explain statements, Explain format=tree, and Explain format=json are included.