Programmatic API

Batch Operations

Multiple writes and command error handling are supported. MergeTree does not enforce primary-key uniqueness, so duplicate IDs do not cause a primary-key conflict error. Do not use batch insert errors to detect duplicates; see Duplicate Record Handling.

A completed batch call does not mean asynchronous mutations have finished. For read-after-write access, see Waiting for Data Changes.

Multiple Results

The JDBC driver does not support collecting results from multiple commands with multipleExecute, or the CallableStatement used by call. Execute queries separately with methods such as queryForObject and queryForList.

Stored Procedures and Functions

Scalar functions in SELECT and table functions in FROM are supported. Stored procedure calls, CallableStatement callbacks, and records returned through OUT parameters are not supported. See Function Queries for positional parameters, named parameters, and examples.