Implement PreparedStmt on the Server side

[Young-Leo]

Implement PreparedStmt on the Server side, including AST cache and memory management.

[Copilot]

Pull request overview

This PR implements server-side prepared statement functionality for the IoTDB relational model, enabling SQL statement preparation, execution, and deallocation. The implementation includes AST caching to avoid re-parsing on execution and memory management through the CoordinatorMemoryManager.

• Adds grammar support for PREPARE, EXECUTE, EXECUTE IMMEDIATE, and DEALLOCATE statements
• Implements AST caching and memory tracking for prepared statements with session-scoped storage
• Integrates parameter binding for prepared statements with proper validation

Reviewed changes

Copilot reviewed 26 out of 26 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
RelationalSql.g4	Adds ANTLR grammar rules for prepared statement syntax
AstBuilder.java	Implements visitor methods to build AST nodes for prepared statements
Prepare.java, Execute.java, ExecuteImmediate.java, Deallocate.java	New AST node classes representing prepared statement operations
AstVisitor.java	Adds visitor methods for new prepared statement AST nodes
ParameterExtractor.java	Utility for extracting and binding parameters in prepared statements
AstMemoryEstimator.java	Estimates memory usage of AST nodes for memory management
PreparedStatementMemoryManager.java	Manages memory allocation/deallocation for prepared statements
PrepareTask.java, DeallocateTask.java	Config tasks for executing PREPARE and DEALLOCATE operations
TableConfigTaskVisitor.java	Routes prepared statement AST nodes to appropriate config tasks
Coordinator.java	Integrates prepared statement execution logic with parameter binding
TableModelPlanner.java	Updated to accept parameters for prepared statement execution
StatementAnalyzer.java	Re-enables parameter support in LIMIT/OFFSET clauses
SessionManager.java	Releases prepared statement memory on session close
BaseServerContextHandler.java	Handles session cleanup on TCP connection loss
IClientSession.java, ClientSession.java, etc.	Adds prepared statement storage to session implementations
PreparedStatementInfo.java	Data class storing prepared statement metadata
IoTDBPreparedStatementIT.java	Integration tests for prepared statement functionality
ClusterTestStatement.java	Documentation for PreparedStatement routing considerations

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[Copilot]

This Statement is not always closed on method exit.

Suggested change

	Statement writeStatement;
	if (connection instanceof ClusterTestConnection) {
	// Use write connection directly for PreparedStatement queries
	writeStatement =
	((ClusterTestConnection) connection)
	.writeConnection
	.getUnderlyingConnection()
	.createStatement();
	} else {
	writeStatement = statement;
	}
	try (ResultSet resultSet = writeStatement.executeQuery(executeSql)) {
	ResultSetMetaData metaData = resultSet.getMetaData();
	// Verify header
	assertEquals(expectedHeader.length, metaData.getColumnCount());
	for (int i = 1; i <= metaData.getColumnCount(); i++) {
	assertEquals(expectedHeader[i - 1], metaData.getColumnName(i));
	}
	// Verify data
	int cnt = 0;
	while (resultSet.next()) {
	StringBuilder builder = new StringBuilder();
	for (int i = 1; i <= expectedHeader.length; i++) {
	builder.append(resultSet.getString(i)).append(",");
	}
	assertEquals(expectedRetArray[cnt], builder.toString());
	cnt++;
	}
	assertEquals(expectedRetArray.length, cnt);
	}
	}
	if (connection instanceof ClusterTestConnection) {
	// Use write connection directly for PreparedStatement queries
	try (Statement writeStatement =
	((ClusterTestConnection) connection)
	.writeConnection
	.getUnderlyingConnection()
	.createStatement();
	ResultSet resultSet = writeStatement.executeQuery(executeSql)) {
	ResultSetMetaData metaData = resultSet.getMetaData();
	// Verify header
	assertEquals(expectedHeader.length, metaData.getColumnCount());
	for (int i = 1; i <= metaData.getColumnCount(); i++) {
	assertEquals(expectedHeader[i - 1], metaData.getColumnName(i));
	}
	// Verify data
	int cnt = 0;
	while (resultSet.next()) {
	StringBuilder builder = new StringBuilder();
	for (int i = 1; i <= expectedHeader.length; i++) {
	builder.append(resultSet.getString(i)).append(",");
	}
	assertEquals(expectedRetArray[cnt], builder.toString());
	cnt++;
	}
	assertEquals(expectedRetArray.length, cnt);
	}
	} else {
	try (ResultSet resultSet = statement.executeQuery(executeSql)) {
	ResultSetMetaData metaData = resultSet.getMetaData();
	// Verify header
	assertEquals(expectedHeader.length, metaData.getColumnCount());
	for (int i = 1; i <= metaData.getColumnCount(); i++) {
	assertEquals(expectedHeader[i - 1], metaData.getColumnName(i));
	}
	// Verify data
	int cnt = 0;
	while (resultSet.next()) {
	StringBuilder builder = new StringBuilder();
	for (int i = 1; i <= expectedHeader.length; i++) {
	builder.append(resultSet.getString(i)).append(",");
	}
	assertEquals(expectedRetArray[cnt], builder.toString());
	cnt++;
	}
	assertEquals(expectedRetArray.length, cnt);
	}
	}

[JackieTien97]

What if user only call PrepareStatement.close?(which will finally call TSStatus closeOperation(TSCloseOperationReq req) ) Did you release the Ast and memory for that case?

[JackieTien97]

throw execption here, mqtt is for write not for query.

[JackieTien97]

Suggested change

	// Map from statement name to PreparedStatementInfo
	private final Map<String, PreparedStatementInfo> preparedStatements = new ConcurrentHashMap<>();

[JackieTien97]

throw exception here, InternalClientSession should never call these methods, they're used for internal query and write which will never use prepare and execute

[JackieTien97]

why did you do this change?

ClientRPCServiceImpl.handleClientExit has already called closeSession(req).