private void parseTimeoutPolicyClause(
      IoTDBSqlParser.TimeoutPolicyClauseContext ctx, CreateContinuousQueryStatement statement) {
    if (ctx.DISCARD() != null) {
      statement.setTimeoutPolicy(TimeoutPolicy.DISCARD);
    }
  }
Check and set datatype, encoding, compressor.

@throws SemanticException if encoding or dataType meets error handling
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/plan/parser/ASTVisitor.java