Flink SQL is a programming language developed by Alibaba Cloud to simplify the computing model of Realtime Compute for Apache Flink and reduce skill requirements for users. Flink SQL complies with standard SQL syntax.
Keywords
Reserved words that cannot be used as identifiers without backtick escaping.
Data views
Create named views to simplify complex queries and reuse query logic across jobs.
DML statements
Write query results to a destination table or create new tables and databases from query output.
DQL statements
Query and transform streaming or batch data using SELECT-based statements.
Window functions
Aggregate data over time-based or count-based windows in streaming jobs.
Built-in functions
Ready-to-use functions for scalar operations, table transformations, and aggregations.
User-defined functions
Extend Flink SQL with custom logic written in Java or Python.
Java
UDSFs — user-defined scalar functions
UDAFs — user-defined aggregate functions
UDTFs — user-defined table functions
Python