# MongoDB to MSSQL database connect and sink **URL:** \ **Category:** Stream Processing\ **Created:** [15 January 2024 13:18 UTC](https://forum.confluent.io/t/mongodb-to-mssql-database-connect-and-sink/9819 "2024-01-15T13:18:13Z")\ **Posts on this page:** 1\ **Page:** 1
**Author:** ![abhiram\_tcig](https://avatars.discourse-cdn.com/v4/letter/a/e480ec/32.png) [@abhiram\_tcig](https://forum.confluent.io/u/abhiram_tcig)\ **Post date:** [15 January 2024 13:18 UTC](https://forum.confluent.io/t/mongodb-to-mssql-database-connect-and-sink/9819/1 "2024-01-15T13:18:14Z")
Hi, I have two databases MongoDB and an MSSQL how to add a realtime database connection between this two what all data I need to taken I have tried this and getting some error while adding the topic to sink connector ```auto org.apache.kafka.connect.errors.ConnectException: Tolerance exceeded in error handler at org.apache.kafka.connect.runtime.errors.RetryWithToleranceOperator.execAndHandleError(RetryWithToleranceOperator.java:223) at org.apache.kafka.connect.runtime.errors.RetryWithToleranceOperator.execute(RetryWithToleranceOperator.java:149) at org.apache.kafka.connect.runtime.WorkerSinkTask.convertAndTransformRecord(WorkerSinkTask.java:513) at org.apache.kafka.connect.runtime.WorkerSinkTask.convertMessages(WorkerSinkTask.java:493) at org.apache.kafka.connect.runtime.WorkerSinkTask.poll(WorkerSinkTask.java:332) at org.apache.kafka.connect.runtime.WorkerSinkTask.iteration(WorkerSinkTask.java:234) at org.apache.kafka.connect.runtime.WorkerSinkTask.execute(WorkerSinkTask.java:203) at org.apache.kafka.connect.runtime.WorkerTask.doRun(WorkerTask.java:189) at org.apache.kafka.connect.runtime.WorkerTask.run(WorkerTask.java:244) at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515) at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264) at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128) at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628) at java.base/java.lang.Thread.run(Thread.java:829) Caused by: org.apache.kafka.connect.errors.DataException: Failed to deserialize data for topic mongo_debezium_test.testdb.usercollection to Avro: at io.confluent.connect.avro.AvroConverter.toConnectData(AvroConverter.java:124) at org.apache.kafka.connect.storage.Converter.toConnectData(Converter.java:88) at org.apache.kafka.connect.runtime.WorkerSinkTask.lambda$convertAndTransformRecord$3(WorkerSinkTask.java:513) at org.apache.kafka.connect.runtime.errors.RetryWithToleranceOperator.execAndRetry(RetryWithToleranceOperator.java:173) at org.apache.kafka.connect.runtime.errors.RetryWithToleranceOperator.execAndHandleError(RetryWithToleranceOperator.java:207) ... 13 more Caused by: org.apache.kafka.common.errors.SerializationException: Unknown magic byte! at io.confluent.kafka.serializers.AbstractKafkaSchemaSerDe.getByteBuffer(AbstractKafkaSchemaSerDe.java:244) at io.confluent.kafka.serializers.AbstractKafkaAvroDeserializer$DeserializationContext.(AbstractKafkaAvroDeserializer.java:334) at io.confluent.kafka.serializers.AbstractKafkaAvroDeserializer.deserializeWithSchemaAndVersion(AbstractKafkaAvroDeserializer.java:202) at io.confluent.connect.avro.AvroConverter$Deserializer.deserialize(AvroConverter.java:172) at io.confluent.connect.avro.AvroConverter.toConnectData(AvroConverter.java:107) ``` ```auto [2024-01-15 07:04:07,026] ERROR WorkerSinkTask{id=mongo_to_mssql_connector-0} Task threw an uncaught and unrecoverable exception. Task is being killed and will not recover until manually restarted (org.apache.kafka.connect.runtime.WorkerTask) org.apache.kafka.connect.errors.ConnectException: Tolerance exceeded in error handler at org.apache.kafka.connect.runtime.errors.RetryWithToleranceOperator.execAndHandleError(RetryWithToleranceOperator.java:223) at org.apache.kafka.connect.runtime.errors.RetryWithToleranceOperator.execute(RetryWithToleranceOperator.java:149) at org.apache.kafka.connect.runtime.TransformationChain.apply(TransformationChain.java:50) at org.apache.kafka.connect.runtime.WorkerSinkTask.convertAndTransformRecord(WorkerSinkTask.java:540) at org.apache.kafka.connect.runtime.WorkerSinkTask.convertMessages(WorkerSinkTask.java:493) at org.apache.kafka.connect.runtime.WorkerSinkTask.poll(WorkerSinkTask.java:332) at org.apache.kafka.connect.runtime.WorkerSinkTask.iteration(WorkerSinkTask.java:234) at org.apache.kafka.connect.runtime.WorkerSinkTask.execute(WorkerSinkTask.java:203) at org.apache.kafka.connect.runtime.WorkerTask.doRun(WorkerTask.java:189) at org.apache.kafka.connect.runtime.WorkerTask.run(WorkerTask.java:244) at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515) at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264) at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128) at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628) at java.base/java.lang.Thread.run(Thread.java:829) Caused by: org.apache.kafka.connect.errors.DataException: Only Struct objects supported for [field extraction], found: java.lang.String at org.apache.kafka.connect.transforms.util.Requirements.requireStruct(Requirements.java:52) at org.apache.kafka.connect.transforms.util.Requirements.requireStructOrNull(Requirements.java:61) at org.apache.kafka.connect.transforms.ExtractField.apply(ExtractField.java:61) at org.apache.kafka.connect.runtime.TransformationChain.lambda$apply$0(TransformationChain.java:50) at org.apache.kafka.connect.runtime.errors.RetryWithToleranceOperator.execAndRetry(RetryWithToleranceOperator.java:173) at org.apache.kafka.connect.runtime.errors.RetryWithToleranceOperator.execAndHandleError(RetryWithToleranceOperator.java:207) ``` this both errors I am getting using the JSON method and Avro