Data Querying
Apache Doris supports standard SQL with strong MySQL compatibility, and on top of that provides high-performance join queries, a rich set of analytic functions, semi-structured data access, and user-defined functions. Choose the documentation that matches your scenario below.
SQL Compatibility
Multi-Table Joins
Joins (JOIN)
JOIN types such as INNER / LEFT / RIGHT / FULL / SEMI / ANTI, along with four distributed JOIN implementations: Broadcast, Shuffle, Bucket Shuffle, and Colocate.
ASOF JOIN for Time-Series Nearest Match
For each row in the left table, find the nearest row in the right table along a time direction, enabling time-series alignment without window functions.
Subqueries
Syntax, restrictions, and Mark Join handling for scalar, non-scalar, correlated, and uncorrelated subqueries.
Common Table Expressions (CTE)
Define temporary result sets with the WITH clause, with support for nested and recursive CTEs, suitable for hierarchy traversal, graph traversal, and similar scenarios.
Aggregation and Analytics
Multi-Dimensional Aggregation Analytics
Use ROLLUP, CUBE, and GROUPING SETS to perform multi-dimensional aggregation analytics in a single SQL statement.
Analytic Functions (Window Functions)
Use the OVER clause to partition and window result sets, supporting ranking, cumulative sums, moving averages, year-over-year and quarter-over-quarter comparisons, and more.
Semi-Structured and Complex Data
Querying Complex Types
Query complex types such as Array, Map, Struct, and JSON, and process semi-structured data with dedicated SQL functions.
Column-to-Row (Lateral View)
Use LATERAL VIEW with generator functions such as EXPLODE to expand a single row into multiple rows, enabling column-to-row SQL queries.
User-Defined Functions (UDF)
Java UDF / UDAF / UDWF / UDTF
Write UDF/UDAF/UDWF/UDTF user-defined functions in Java, including type mapping, registration syntax, best practices, and examples.
Python UDF / UDAF / UDWF / UDTF
Write UDF/UDAF/UDTF in Python: covers creation, vectorization, environment configuration, and common troubleshooting.
Alias Functions
Register a new signature for a function or expression fragment with CREATE ALIAS FUNCTION to improve migration compatibility and simplify writing complex queries.
