topic Re: Copy data Oracle Timezone Issue in Data Engineering

Copy data Oracle Timezone Issue

eleonb — Fri, 12 Dec 2025 12:27:45 GMT

Context / Background

We are using Fabric to copy data from an internal Oracle database via an On-Premises Data Gateway.

The Oracle database has TZFILE version 14 (timezlrg_14.dat). I do not have the ability to modify anything directly in the database.

The connection works from Dataflows, but NOT from a Copy Data Activity in a pipeline, which throws the following error:

ORA-00604: error occurred at recursive SQL level 1 ORA-01882: timezone region not found

The Data Gateway is inside the same corporate network, with UTC time zone.
The connection string being used is standard, for example:

(DESCRIPTION = (FAILOVER=ON) (ADDRESS = (PROTOCOL = TCP)(HOST = 10.xx.xxx.xxx)(PORT = xxxx)) (CONNECT_DATA = (SERVER = DEDICATED)(SERVICE_NAME = xxxxxxx) (FAILOVER_MODE=(TYPE=SESSION)(METHOD=BASIC)) ) )

Investigations / Troubleshooting performed

Gateway server time zone

Confirmed as (UTC) Coordinated Universal Time → correct.

ODP.NET driver (v19) on the gateway server

Tried replacing Oracle.ManagedDataAccess.dll with version 12.2.
Tried creating oracle.manageddataaccess.client.config with UseTZRegion=false.
Nothing solved the problem.

I need to run these queries from a pipeline, since they are very heavy queries that make it very difficult to work with them from Dataflows.

I appreciate any help on this issue. Thank you very much!

Re: Copy data Oracle Timezone Issue

Zanqueta — Fri, 12 Dec 2025 15:34:07 GMT

This is a known issue when connecting to Oracle via ODP.NET in environments where the timezone region mapping is not fully supported by the Oracle client or the gateway configuration. The error:

ORA-00604: error occurred at recursive SQL level 1
ORA-01882: timezone region not found

occurs because Oracle tries to resolve the timezone region from the client session, and the region is not recognised by the database's TZFILE version.

Why Dataflows Work but Pipelines Fail

Dataflows use Power Query connectors that handle timezone differently (often defaulting to UTC).
Pipelines with Copy Data rely on the ODP.NET driver and pass the client timezone region, which Oracle cannot resolve.

✅ Workarounds

Since you cannot modify the database, you need to adjust the client-side behaviour:

Option 1: Force UTC in the Connection

Add the following to your connection string:

;Connection Timeout=30;Validate Connection=true;DefaultTimeZone=UTC

or explicitly set:

ALTER SESSION SET TIME_ZONE = 'UTC';

You can run this as a Pre-copy script in the Copy Data activity:

ALTER SESSION SET TIME_ZONE = 'UTC';

This avoids Oracle trying to resolve the region from the client.

Option 2: Use UseTZRegion=false in ODP.NET Config

You mentioned trying this, but ensure:

The file oracle.manageddataaccess.client.config is in the same directory as the gateway executable.
It contains:

Restart the gateway after applying this.

Option 3: Upgrade Oracle Client

If possible, use ODP.NET Managed Driver v21 or later, as older versions have known issues with TZFILE compatibility.

Why Groups or Service Principals Are Not Relevant Here

This is purely a timezone resolution issue, not an authentication problem.

Reference:

Copy data to and from Oracle - Azure Data Factory & Azure Synapse | Microsoft Learn

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Please mark it as the correct solution. It helps other community members find their way faster (and saves them from another endless loop 🌀.

Re: Copy data Oracle Timezone Issue

eleonb — Sat, 13 Dec 2025 08:57:30 GMT

Thanks for the response!

After extensive testing, it looks like this is a limitation of the OracleV2 driver used by Fabric Copy Activity.

The activity copy data does not allow pre-copy scripts, does not respect ODP.NET configuration files, and does not use the Oracle client installed on the gateway , I suspect Fabric use its own driver located in the datagateway server in FabricIntegrationRuntime\...\sxs\OracleV2Unbundle. Also in the connection configuration I cannot include the options you mention in the connection string, given that Fabric only let me put the Oracle Descriptor inside the Server field when creating the connection.

As a result, there is no supported way to force UTC or disable timezone region mapping when connecting to Oracle databases using TZFILE 14.

Dataflows work because they use a different connector that handles timezones differently as you mention.

Re: Copy data Oracle Timezone Issue

v-echaithra — Thu, 18 Dec 2025 06:30:24 GMT

Hi @eleonb ,

Thank you for sharing the detailed findings and for taking the time to thoroughly investigate this behavior. As this is a current limitation of the OracleV2 connector used by Fabric Copy Data activities, which does not support pre-copy scripts, custom ODP.NET configurations, or external Oracle client settings on the gateway. We appreciate you clearly outlining the differences in behavior between Dataflows and Pipelines, as this information will be valuable for other customers encountering similar scenarios. We recommend submitting this as a feature request here Fabric Ideas - Microsoft Fabric Community so the product team can evaluate support for enhanced timezone handling in future updates.

Best Regards,
Chaithra E.

Re: Copy data Oracle Timezone Issue

v-echaithra — Mon, 22 Dec 2025 11:25:27 GMT

Hi @eleonb ,

Thank you @Zanqueta for your inputs.

I just wanted to check if the issue has been resolved on your end, or if you require any further assistance. Please feel free to let us know, we’re happy to help!

Thank you
Chaithra E.