Airbyte MSSQL → MSSQL: Tables are created but no data is replicated (0 rows) – silent behavior with non-dbo schema and Full Refresh

[sospixs]

All details is below

Environment
• Airbyte: self-managed
• Airbyte version: 2.0.1
• OS: Ubuntu (IaaS)
• Source: Microsoft SQL Server 2016 Standard
• Destination: Microsoft SQL Server 2016 Standard
• Network: same internal network (connectivity confirmed)

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Test Setup
• Source table: DB_SOURCE.dbo.iCS_Customer_PK
• Destination database: DB_AIRBYTE
• Rows in source table: ~2,000
• Primary Key: Yes (explicit PK created for testing)
• Sync mode tested:
o Full refresh | Overwrite
o Incremental | Append
o Incremental | Append + Deduped
• Connection state reset attempts:
o Clear your data
o Refresh your data (reset state)

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Observed Behavior

1. Source connector
   o Connection check: ✅ success
   o Schema discovery: ✅ success
   o Tables and columns are detected correctly
2. Destination behavior
   o When destination schema is set to dbo:
    Table is created
    airbyte* metadata columns are created
    No data rows are inserted (0 rows)
   o When destination schema is set to a non-dbo schema (e.g. abt):
    Schema is created
    Table is NOT created at all
    No errors reported
3. Sync execution
   o Sync runs for a long time and completes
   o No errors in logs
   o Logs do NOT show any SELECT / FETCH / EMITTED RECORDS
   o Job appears successful from Airbyte’s perspective
4. Result
   o Destination ends up with:
    Table structure only (when using dbo)
    Or only schema without tables (when using non-dbo)
   o No data is ever replicated

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Key Findings / Suspicions
• This does not appear to be:
o Network related
o Permission denial with explicit errors
o Missing Primary Key
o Incremental cursor misconfiguration
o Connection state issue
• Behavior strongly suggests:
o A limitation or bug in the MSSQL destination connector
o Especially related to:
 Non-dbo schemas
 Default schema handling of the database user
 Silent failures during INSERT / write phase
o Connector creates schemas and tables but does not actually write data, without raising errors

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Expected Behavior
• For Full refresh | Overwrite:
o Tables should be created
o All rows from source should be inserted into destination
o If writes fail, an explicit error should be raised

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Actual Behavior
• Tables may be created
• No data is written
• No error or warning is surfaced
• Sync is marked as successful but it take 40 minutes to complete!

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Why This Is a Problem
• Silent success makes the issue extremely hard to detect
• From an operator perspective, the pipeline appears healthy
• High risk in production usage, especially for MSSQL → MSSQL replication

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