Make Connection.setReadOnly a no-op instead of throwing#1523
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Connection.setReadOnly(true) threw DatabricksSQLFeatureNotSupportedException, which broke JDBC clients that call it during connection initialization (e.g. Trino/Starburst GenericJDBC connector, HikariCP, DBCP). Per the JDBC spec, setReadOnly is a hint used to enable database optimizations and may be ignored by drivers that do not enforce a connection-level read-only mode. The Databricks backend does not enforce read-only mode, so setReadOnly is now a no-op and isReadOnly() continues to report false since the hint is not enforced. Co-authored-by: Isaac Signed-off-by: Vikrant Puppala <vikrant.puppala@databricks.com>
gopalldb
approved these changes
Jul 2, 2026
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Summary
Connection.setReadOnly(true)threwDatabricksSQLFeatureNotSupportedException, which breaks JDBC clients that callsetReadOnly(true)during connection initialization — e.g. the Trino/Starburst GenericJDBC connector, HikariCP, and DBCP connection pools. This was reported via an internal support thread for a Starburst GenericJDBC integration.Per the JDBC spec,
setReadOnlyis a hint used to enable database optimizations; a driver that does not enforce a connection-level read-only mode is permitted to ignore it. The Databricks backend does not enforce read-only mode, so throwing here is non-conformant.Fix
setReadOnly(true)is now a no-op (it still validates the connection is open, matching the prior behavior ofthrowExceptionIfConnectionIsClosed()).isReadOnly()continues to returnfalse, since the hint is not actually enforced — this remains accurate.Test plan
DatabricksConnectionTest#testReadOnlyAndAbort:setReadOnly(false)— no throw (unchanged)setReadOnly(true)— now asserts no throw (was previously assertingDatabricksSQLFeatureNotSupportedException)isReadOnly()still returnsfalseDatabricksConnectionTestclass — all pass.isReadOnly()on a closed connection still throwsDatabricksSQLException(existing test at line 353).NO_CHANGELOG=false