You are viewing a plain text version of this content. The canonical link for it is here.
Posted to notifications@superset.apache.org by "Dhruvin4530 (via GitHub)" <gi...@apache.org> on 2025/09/18 13:08:14 UTC
[D] Superset is not able to recognise the NULL datatype of any column [superset]
GitHub user Dhruvin4530 created a discussion: Superset is not able to recognise the NULL datatype of any column
I am using hydrolix connector to fetch the columns from events table which is in hydrolix. There is a column called timestamp. The data type of timestamp is NULL in hydrolix and in superset when I fetched the columns using dataset the datatype is showing UNKNOWN for timestamp column and due to that the time rang query is not working and charts are not loading.
GitHub link: https://github.com/apache/superset/discussions/35188
----
This is an automatically sent email for notifications@superset.apache.org.
To unsubscribe, please send an email to: notifications-unsubscribe@superset.apache.org
---------------------------------------------------------------------
To unsubscribe, e-mail: notifications-unsubscribe@superset.apache.org
For additional commands, e-mail: notifications-help@superset.apache.org
Re: [D] Superset is not able to recognise the NULL datatype of any column [superset]
Posted by "dosubot[bot] (via GitHub)" <gi...@apache.org>.
GitHub user dosubot[bot] added a comment to the discussion: Superset is not able to recognise the NULL datatype of any column
<!-- Answer -->
The difference is likely due to stricter validation or changes in dependencies (like SQLAlchemy or database drivers) in Superset 3.0.0, not a change in Superset's core logic. In both 2.1.0 and 3.0.0, if a column's type is NULL or missing, Superset marks it as UNKNOWN and can't use it for time-based features. However, 3.0.0 introduced stricter handling for time columns, so ambiguous or missing types that may have been tolerated in 2.1.0 now cause issues in 3.0.0. There were also regressions in 3.0.0 related to time column recognition that were fixed in 3.0.2 ([discussion](https://github.com/apache/superset/issues/22774), [related thread](https://github.com/apache/superset/discussions/35135)).
To avoid this, make sure your timestamp column in Hydrolix has an explicit datetime type. If you can't change the schema, you would need to patch the connector or engine spec to handle NULL types, but Superset itself can't recognize NULL as a valid temporal type in any recent version ([code reference](https://github.com/apache/superset/blob/829e4d92d91ceae4b43b1ed3b063ffe45377799c/superset/connectors/sqla/utils.py)).
<!-- Dosu Comment Footer -->
*To reply, just mention [@dosu](https://go.dosu.dev/dosubot).*
---
<sup>How did I do? [Good](https://app.dosu.dev/response-feedback/29f07be7-a475-48e7-822b-084828182d96?feedback_type=great_response) | [Irrelevant](https://app.dosu.dev/response-feedback/29f07be7-a475-48e7-822b-084828182d96?feedback_type=irrelevant_answer) | [Incorrect](https://app.dosu.dev/response-feedback/29f07be7-a475-48e7-822b-084828182d96?feedback_type=incorrect_sources) | [Verbose](https://app.dosu.dev/response-feedback/29f07be7-a475-48e7-822b-084828182d96?feedback_type=too_verbose) | [Hallucination](https://app.dosu.dev/response-feedback/29f07be7-a475-48e7-822b-084828182d96?feedback_type=hallucination) | [Report 🐛](https://app.dosu.dev/response-feedback/29f07be7-a475-48e7-822b-084828182d96?feedback_type=bug_report) | [Other](https://app.dosu.dev/response-feedback/29f07be7-a475-48e7-822b-084828182d96?feedback_type=other)</sup> [](https://app.dosu.dev/a28d3c7e-a9d3-459e-9fb6-3a6f9ff4f357/ask?utm_source=github)&
nbsp;[](https://go.dosu.dev/discord-bot) [](https://twitter.com/intent/tweet?text=%40dosu_ai%20helped%20me%20solve%20this%20issue!&url=https%3A//github.com/apache/superset/discussions/35188)
GitHub link: https://github.com/apache/superset/discussions/35188#discussioncomment-14443904
----
This is an automatically sent email for notifications@superset.apache.org.
To unsubscribe, please send an email to: notifications-unsubscribe@superset.apache.org
---------------------------------------------------------------------
To unsubscribe, e-mail: notifications-unsubscribe@superset.apache.org
For additional commands, e-mail: notifications-help@superset.apache.org
Re: [D] Superset is not able to recognise the NULL datatype of any column [superset]
Posted by "dosubot[bot] (via GitHub)" <gi...@apache.org>.
GitHub user dosubot[bot] edited a comment on the discussion: Superset is not able to recognise the NULL datatype of any column
<!-- Answer -->
Superset needs the timestamp column to have a recognized datetime type from Hydrolix; if the type is NULL, Superset marks it as UNKNOWN and disables time-based features. The most reliable fix is to update your Hydrolix table schema so the timestamp column has an explicit datetime type (like TIMESTAMP or DATETIME). After that, refresh the dataset metadata in Superset and set the main datetime column in the dataset editor if needed. If you can't change the schema, you would need to patch the connector's engine spec to handle NULL types, but that's a backend code change.
If this works in another Superset instance with the same config, compare your Superset and connector versions—upgrading may help, as newer versions have improved time column handling. There is no UI or API workaround for this; manual changes in Superset won't work if the database still reports NULL for the column type.
[Reference: Superset code and engine spec handling](https://github.com/apache/superset/blob/829e4d92d91ceae4b43b1ed3b063ffe45377799c/superset/connectors/sqla/utils.py)
[Related discussion](https://github.com/apache/superset/discussions/35135)
<!-- Dosu Comment Footer -->
*To reply, just mention [@dosu](https://go.dosu.dev/dosubot?utm_source=github&utm_medium=bot-comment&utm_campaign=github-comment-footer-20260415&utm_content=reply-with-mention&utm_term=apache%2Fsuperset).*
---
Share context across your team and agents. Try [Dosu](https://dosu.dev?utm_source=github&utm_medium=bot-comment&utm_campaign=github-comment-footer-20260415&utm_content=knowledge-infrastructure-tagline&utm_term=apache%2Fsuperset).
[](https://app.dosu.dev/response-feedback?utm_source=github&utm_medium=bot-comment&utm_campaign=github-comment-footer-20260415&utm_content=knowledge-infrastructure-feedback&utm_term=apache%2Fsuperset&message_id=243496a5-5a29-4a55-b9af-ad65d2596bd4) [](https://github.dosu.com/apache/superset?utm_source=github&utm_medium=bot-comment&utm_campaign=github-comment-footer-20260415&utm_content=knowledge-infrastructure-learn-repo&utm_term=apache%2Fsuperset) [](https://app.dosu.dev/signup?referrer=openSource&source=github-footer&utm_source=github&utm_medium=bot-comment&utm_campaign=github-comment-footer-20260415&utm_content=knowledge-infrastructure-add-team&utm_term=apache%2Fsuperset)
GitHub link: https://github.com/apache/superset/discussions/35188#discussioncomment-14443443
----
This is an automatically sent email for notifications@superset.apache.org.
To unsubscribe, please send an email to: notifications-unsubscribe@superset.apache.org
---------------------------------------------------------------------
To unsubscribe, e-mail: notifications-unsubscribe@superset.apache.org
For additional commands, e-mail: notifications-help@superset.apache.org
Re: [D] Superset is not able to recognise the NULL datatype of any column [superset]
Posted by "Dhruvin4530 (via GitHub)" <gi...@apache.org>.
GitHub user Dhruvin4530 added a comment to the discussion: Superset is not able to recognise the NULL datatype of any column
My one of the superset instance is on 2.1.0 version and I am using hydrolix (clickhouse) connector to fetch the columns and the datatype of timestamp column is null and it is working
GitHub link: https://github.com/apache/superset/discussions/35188#discussioncomment-14443952
----
This is an automatically sent email for notifications@superset.apache.org.
To unsubscribe, please send an email to: notifications-unsubscribe@superset.apache.org
---------------------------------------------------------------------
To unsubscribe, e-mail: notifications-unsubscribe@superset.apache.org
For additional commands, e-mail: notifications-help@superset.apache.org
Re: [D] Superset is not able to recognise the NULL datatype of any column [superset]
Posted by "dosubot[bot] (via GitHub)" <gi...@apache.org>.
GitHub user dosubot[bot] edited a comment on the discussion: Superset is not able to recognise the NULL datatype of any column
<!-- Answer -->
The difference is likely due to stricter validation or changes in dependencies (like SQLAlchemy or database drivers) in Superset 3.0.0, not a change in Superset's core logic. In both 2.1.0 and 3.0.0, if a column's type is NULL or missing, Superset marks it as UNKNOWN and can't use it for time-based features. However, 3.0.0 introduced stricter handling for time columns, so ambiguous or missing types that may have been tolerated in 2.1.0 now cause issues in 3.0.0. There were also regressions in 3.0.0 related to time column recognition that were fixed in 3.0.2 ([discussion](https://github.com/apache/superset/issues/22774), [related thread](https://github.com/apache/superset/discussions/35135)).
To avoid this, make sure your timestamp column in Hydrolix has an explicit datetime type. If you can't change the schema, you would need to patch the connector or engine spec to handle NULL types, but Superset itself can't recognize NULL as a valid temporal type in any recent version ([code reference](https://github.com/apache/superset/blob/829e4d92d91ceae4b43b1ed3b063ffe45377799c/superset/connectors/sqla/utils.py)).
<!-- Dosu Comment Footer -->
*To reply, just mention [@dosu](https://go.dosu.dev/dosubot?utm_source=github&utm_medium=bot-comment&utm_campaign=github-comment-footer-20260415&utm_content=reply-with-mention&utm_term=apache%2Fsuperset).*
---
Share context across your team and agents. Try [Dosu](https://dosu.dev?utm_source=github&utm_medium=bot-comment&utm_campaign=github-comment-footer-20260415&utm_content=knowledge-infrastructure-tagline&utm_term=apache%2Fsuperset).
[](https://app.dosu.dev/response-feedback?utm_source=github&utm_medium=bot-comment&utm_campaign=github-comment-footer-20260415&utm_content=knowledge-infrastructure-feedback&utm_term=apache%2Fsuperset&message_id=29f07be7-a475-48e7-822b-084828182d96) [](https://github.dosu.com/apache/superset?utm_source=github&utm_medium=bot-comment&utm_campaign=github-comment-footer-20260415&utm_content=knowledge-infrastructure-learn-repo&utm_term=apache%2Fsuperset) [](https://app.dosu.dev/signup?referrer=openSource&source=github-footer&utm_source=github&utm_medium=bot-comment&utm_campaign=github-comment-footer-20260415&utm_content=knowledge-infrastructure-add-team&utm_term=apache%2Fsuperset)
GitHub link: https://github.com/apache/superset/discussions/35188#discussioncomment-14443904
----
This is an automatically sent email for notifications@superset.apache.org.
To unsubscribe, please send an email to: notifications-unsubscribe@superset.apache.org
---------------------------------------------------------------------
To unsubscribe, e-mail: notifications-unsubscribe@superset.apache.org
For additional commands, e-mail: notifications-help@superset.apache.org
Re: [D] Superset is not able to recognise the NULL datatype of any column [superset]
Posted by "Dhruvin4530 (via GitHub)" <gi...@apache.org>.
GitHub user Dhruvin4530 added a comment to the discussion: Superset is not able to recognise the NULL datatype of any column
@dosu What should I do now?
GitHub link: https://github.com/apache/superset/discussions/35188#discussioncomment-14443402
----
This is an automatically sent email for notifications@superset.apache.org.
To unsubscribe, please send an email to: notifications-unsubscribe@superset.apache.org
---------------------------------------------------------------------
To unsubscribe, e-mail: notifications-unsubscribe@superset.apache.org
For additional commands, e-mail: notifications-help@superset.apache.org
Re: [D] Superset is not able to recognise the NULL datatype of any column [superset]
Posted by "Dhruvin4530 (via GitHub)" <gi...@apache.org>.
GitHub user Dhruvin4530 edited a comment on the discussion: Superset is not able to recognise the NULL datatype of any column
@dosu My one of the superset instance is on 2.1.0 version and I am using hydrolix (clickhouse) connector to fetch the columns and the datatype of timestamp column is null and it is working
GitHub link: https://github.com/apache/superset/discussions/35188#discussioncomment-14443952
----
This is an automatically sent email for notifications@superset.apache.org.
To unsubscribe, please send an email to: notifications-unsubscribe@superset.apache.org
---------------------------------------------------------------------
To unsubscribe, e-mail: notifications-unsubscribe@superset.apache.org
For additional commands, e-mail: notifications-help@superset.apache.org
Re: [D] Superset is not able to recognise the NULL datatype of any column [superset]
Posted by "dosubot[bot] (via GitHub)" <gi...@apache.org>.
GitHub user dosubot[bot] added a comment to the discussion: Superset is not able to recognise the NULL datatype of any column
<!-- Answer -->
Superset needs the timestamp column to have a recognized datetime type from Hydrolix; if the type is NULL, Superset marks it as UNKNOWN and disables time-based features. The most reliable fix is to update your Hydrolix table schema so the timestamp column has an explicit datetime type (like TIMESTAMP or DATETIME). After that, refresh the dataset metadata in Superset and set the main datetime column in the dataset editor if needed. If you can't change the schema, you would need to patch the connector's engine spec to handle NULL types, but that's a backend code change.
If this works in another Superset instance with the same config, compare your Superset and connector versions—upgrading may help, as newer versions have improved time column handling. There is no UI or API workaround for this; manual changes in Superset won't work if the database still reports NULL for the column type.
[Reference: Superset code and engine spec handling](https://github.com/apache/superset/blob/829e4d92d91ceae4b43b1ed3b063ffe45377799c/superset/connectors/sqla/utils.py)
[Related discussion](https://github.com/apache/superset/discussions/35135)
<!-- Dosu Comment Footer -->
*To reply, just mention [@dosu](https://go.dosu.dev/dosubot).*
---
<sup>How did I do? [Good](https://app.dosu.dev/response-feedback/243496a5-5a29-4a55-b9af-ad65d2596bd4?feedback_type=great_response) | [Irrelevant](https://app.dosu.dev/response-feedback/243496a5-5a29-4a55-b9af-ad65d2596bd4?feedback_type=irrelevant_answer) | [Incorrect](https://app.dosu.dev/response-feedback/243496a5-5a29-4a55-b9af-ad65d2596bd4?feedback_type=incorrect_sources) | [Verbose](https://app.dosu.dev/response-feedback/243496a5-5a29-4a55-b9af-ad65d2596bd4?feedback_type=too_verbose) | [Hallucination](https://app.dosu.dev/response-feedback/243496a5-5a29-4a55-b9af-ad65d2596bd4?feedback_type=hallucination) | [Report 🐛](https://app.dosu.dev/response-feedback/243496a5-5a29-4a55-b9af-ad65d2596bd4?feedback_type=bug_report) | [Other](https://app.dosu.dev/response-feedback/243496a5-5a29-4a55-b9af-ad65d2596bd4?feedback_type=other)</sup> [](https://app.dosu.dev/a28d3c7e-a9d3-459e-9fb6-3a6f9ff4f357/ask?utm_source=github)&
nbsp;[](https://go.dosu.dev/discord-bot) [](https://twitter.com/intent/tweet?text=%40dosu_ai%20helped%20me%20solve%20this%20issue!&url=https%3A//github.com/apache/superset/discussions/35188)
GitHub link: https://github.com/apache/superset/discussions/35188#discussioncomment-14443443
----
This is an automatically sent email for notifications@superset.apache.org.
To unsubscribe, please send an email to: notifications-unsubscribe@superset.apache.org
---------------------------------------------------------------------
To unsubscribe, e-mail: notifications-unsubscribe@superset.apache.org
For additional commands, e-mail: notifications-help@superset.apache.org
Re: [D] Superset is not able to recognise the NULL datatype of any column [superset]
Posted by "Dhruvin4530 (via GitHub)" <gi...@apache.org>.
GitHub user Dhruvin4530 added a comment to the discussion: Superset is not able to recognise the NULL datatype of any column
@dosu Why superset version 2.1.0 is able to recognise the NULL datatype and why 3.0.0 version not?
GitHub link: https://github.com/apache/superset/discussions/35188#discussioncomment-14443867
----
This is an automatically sent email for notifications@superset.apache.org.
To unsubscribe, please send an email to: notifications-unsubscribe@superset.apache.org
---------------------------------------------------------------------
To unsubscribe, e-mail: notifications-unsubscribe@superset.apache.org
For additional commands, e-mail: notifications-help@superset.apache.org
Re: [D] Superset is not able to recognise the NULL datatype of any column [superset]
Posted by "Dhruvin4530 (via GitHub)" <gi...@apache.org>.
GitHub user Dhruvin4530 added a comment to the discussion: Superset is not able to recognise the NULL datatype of any column
@dosu My one of the superset instance is on 2.1.0 version and I am using hydrolix (clickhouse) connector to fetch the columns and the datatype of timestamp column is null and it is working
GitHub link: https://github.com/apache/superset/discussions/35188#discussioncomment-14444001
----
This is an automatically sent email for notifications@superset.apache.org.
To unsubscribe, please send an email to: notifications-unsubscribe@superset.apache.org
---------------------------------------------------------------------
To unsubscribe, e-mail: notifications-unsubscribe@superset.apache.org
For additional commands, e-mail: notifications-help@superset.apache.org
Re: [D] Superset is not able to recognise the NULL datatype of any column [superset]
Posted by "dosubot[bot] (via GitHub)" <gi...@apache.org>.
GitHub user dosubot[bot] added a comment to the discussion: Superset is not able to recognise the NULL datatype of any column
<!-- Answer -->
Superset shows the `timestamp` column as UNKNOWN because the Hydrolix connector (or the underlying database) reports its datatype as NULL. Superset relies on the connector to provide explicit type information; if the type is NULL or ambiguous, Superset can't map it to a recognized type and marks it as UNKNOWN, which breaks time-based features like time range queries and chart rendering. There isn't a built-in way in Superset to manually override or fix this in the UI or API—column types are inferred directly from the database metadata and engine spec mappings.
To resolve this, make sure the source database (Hydrolix) provides an explicit and correct type for the `timestamp` column. Alternatively, you could patch the engine spec for the Hydrolix connector to handle NULL or ambiguous types more gracefully, but this requires backend code changes. Superset does not have Hydrolix-specific logic for this and uses the generic SQLAlchemy pathway for type inference. If the column remains UNKNOWN, it cannot be used for time filters or as a temporal column in charts.
[Reference: Superset code and engine spec handling](https://github.com/apache/superset/blob/829e4d92d91ceae4b43b1ed3b063ffe45377799c/superset/connectors/sqla/utils.py)
<!-- Dosu Comment Footer -->
*To reply, just mention [@dosu](https://go.dosu.dev/dosubot).*
---
<sup>How did I do? [Good](https://app.dosu.dev/response-feedback/805e81b9-279e-4139-b24c-402c81f5421c?feedback_type=great_response) | [Irrelevant](https://app.dosu.dev/response-feedback/805e81b9-279e-4139-b24c-402c81f5421c?feedback_type=irrelevant_answer) | [Incorrect](https://app.dosu.dev/response-feedback/805e81b9-279e-4139-b24c-402c81f5421c?feedback_type=incorrect_sources) | [Verbose](https://app.dosu.dev/response-feedback/805e81b9-279e-4139-b24c-402c81f5421c?feedback_type=too_verbose) | [Hallucination](https://app.dosu.dev/response-feedback/805e81b9-279e-4139-b24c-402c81f5421c?feedback_type=hallucination) | [Report 🐛](https://app.dosu.dev/response-feedback/805e81b9-279e-4139-b24c-402c81f5421c?feedback_type=bug_report) | [Other](https://app.dosu.dev/response-feedback/805e81b9-279e-4139-b24c-402c81f5421c?feedback_type=other)</sup> [](https://app.dosu.dev/a28d3c7e-a9d3-459e-9fb6-3a6f9ff4f357/ask?utm_source=github)&
nbsp;[](https://go.dosu.dev/discord-bot) [](https://twitter.com/intent/tweet?text=%40dosu_ai%20helped%20me%20solve%20this%20issue!&url=https%3A//github.com/apache/superset/discussions/35188)
GitHub link: https://github.com/apache/superset/discussions/35188#discussioncomment-14443377
----
This is an automatically sent email for notifications@superset.apache.org.
To unsubscribe, please send an email to: notifications-unsubscribe@superset.apache.org
---------------------------------------------------------------------
To unsubscribe, e-mail: notifications-unsubscribe@superset.apache.org
For additional commands, e-mail: notifications-help@superset.apache.org
Re: [D] Superset is not able to recognise the NULL datatype of any column [superset]
Posted by "dosubot[bot] (via GitHub)" <gi...@apache.org>.
GitHub user dosubot[bot] added a comment to the discussion: Superset is not able to recognise the NULL datatype of any column
<!-- Answer -->
Superset 2.1.0 and 3.0.0 both rely on the database connector and engine spec to infer column types. If the database reports a NULL or missing type for a column, Superset marks it as UNKNOWN and normally disables time-based features for that column. There is no special logic in 2.1.0 to treat NULL types as temporal—recognition depends on the type string and engine spec mapping. The fact that your 2.1.0 instance works with a NULL timestamp column is likely due to differences in the metadata returned by the database or connector, or possibly looser validation in dependencies like SQLAlchemy at that time. In 3.0.0, stricter validation or changes in dependencies mean that ambiguous or NULL types are no longer tolerated, so the column is marked as UNKNOWN and can't be used for time filters or charts. The core logic for type inference hasn't changed between these versions; the difference is likely environmental or due to dependency updates, not a deliberate change in Superset itself.
[Reference: Superset 2.1.0 column type inference and engine spec logic](https://github.com/apache/superset/blob/829e4d92d91ceae4b43b1ed3b063ffe45377799c/superset/connectors/sqla/utils.py)
<!-- Dosu Comment Footer -->
*To reply, just mention [@dosu](https://go.dosu.dev/dosubot).*
---
<sup>How did I do? [Good](https://app.dosu.dev/response-feedback/ada30563-213a-4ed8-9bab-097c4d070b4d?feedback_type=great_response) | [Irrelevant](https://app.dosu.dev/response-feedback/ada30563-213a-4ed8-9bab-097c4d070b4d?feedback_type=irrelevant_answer) | [Incorrect](https://app.dosu.dev/response-feedback/ada30563-213a-4ed8-9bab-097c4d070b4d?feedback_type=incorrect_sources) | [Verbose](https://app.dosu.dev/response-feedback/ada30563-213a-4ed8-9bab-097c4d070b4d?feedback_type=too_verbose) | [Hallucination](https://app.dosu.dev/response-feedback/ada30563-213a-4ed8-9bab-097c4d070b4d?feedback_type=hallucination) | [Report 🐛](https://app.dosu.dev/response-feedback/ada30563-213a-4ed8-9bab-097c4d070b4d?feedback_type=bug_report) | [Other](https://app.dosu.dev/response-feedback/ada30563-213a-4ed8-9bab-097c4d070b4d?feedback_type=other)</sup> [](https://app.dosu.dev/a28d3c7e-a9d3-459e-9fb6-3a6f9ff4f357/ask?utm_source=github)&
nbsp;[](https://go.dosu.dev/discord-bot) [](https://twitter.com/intent/tweet?text=%40dosu_ai%20helped%20me%20solve%20this%20issue!&url=https%3A//github.com/apache/superset/discussions/35188)
GitHub link: https://github.com/apache/superset/discussions/35188#discussioncomment-14444036
----
This is an automatically sent email for notifications@superset.apache.org.
To unsubscribe, please send an email to: notifications-unsubscribe@superset.apache.org
---------------------------------------------------------------------
To unsubscribe, e-mail: notifications-unsubscribe@superset.apache.org
For additional commands, e-mail: notifications-help@superset.apache.org
Re: [D] Superset is not able to recognise the NULL datatype of any column [superset]
Posted by "dosubot[bot] (via GitHub)" <gi...@apache.org>.
GitHub user dosubot[bot] edited a comment on the discussion: Superset is not able to recognise the NULL datatype of any column
<!-- Answer -->
Superset shows the `timestamp` column as UNKNOWN because the Hydrolix connector (or the underlying database) reports its datatype as NULL. Superset relies on the connector to provide explicit type information; if the type is NULL or ambiguous, Superset can't map it to a recognized type and marks it as UNKNOWN, which breaks time-based features like time range queries and chart rendering. There isn't a built-in way in Superset to manually override or fix this in the UI or API—column types are inferred directly from the database metadata and engine spec mappings.
To resolve this, make sure the source database (Hydrolix) provides an explicit and correct type for the `timestamp` column. Alternatively, you could patch the engine spec for the Hydrolix connector to handle NULL or ambiguous types more gracefully, but this requires backend code changes. Superset does not have Hydrolix-specific logic for this and uses the generic SQLAlchemy pathway for type inference. If the column remains UNKNOWN, it cannot be used for time filters or as a temporal column in charts.
[Reference: Superset code and engine spec handling](https://github.com/apache/superset/blob/829e4d92d91ceae4b43b1ed3b063ffe45377799c/superset/connectors/sqla/utils.py)
<!-- Dosu Comment Footer -->
*To reply, just mention [@dosu](https://go.dosu.dev/dosubot?utm_source=github&utm_medium=bot-comment&utm_campaign=github-comment-footer-20260415&utm_content=reply-with-mention&utm_term=apache%2Fsuperset).*
---
Share context across your team and agents. Try [Dosu](https://dosu.dev?utm_source=github&utm_medium=bot-comment&utm_campaign=github-comment-footer-20260415&utm_content=knowledge-infrastructure-tagline&utm_term=apache%2Fsuperset).
[](https://app.dosu.dev/response-feedback?utm_source=github&utm_medium=bot-comment&utm_campaign=github-comment-footer-20260415&utm_content=knowledge-infrastructure-feedback&utm_term=apache%2Fsuperset&message_id=805e81b9-279e-4139-b24c-402c81f5421c) [](https://github.dosu.com/apache/superset?utm_source=github&utm_medium=bot-comment&utm_campaign=github-comment-footer-20260415&utm_content=knowledge-infrastructure-learn-repo&utm_term=apache%2Fsuperset) [](https://app.dosu.dev/signup?referrer=openSource&source=github-footer&utm_source=github&utm_medium=bot-comment&utm_campaign=github-comment-footer-20260415&utm_content=knowledge-infrastructure-add-team&utm_term=apache%2Fsuperset)
GitHub link: https://github.com/apache/superset/discussions/35188#discussioncomment-14443377
----
This is an automatically sent email for notifications@superset.apache.org.
To unsubscribe, please send an email to: notifications-unsubscribe@superset.apache.org
---------------------------------------------------------------------
To unsubscribe, e-mail: notifications-unsubscribe@superset.apache.org
For additional commands, e-mail: notifications-help@superset.apache.org
Re: [D] Superset is not able to recognise the NULL datatype of any column [superset]
Posted by "dosubot[bot] (via GitHub)" <gi...@apache.org>.
GitHub user dosubot[bot] edited a comment on the discussion: Superset is not able to recognise the NULL datatype of any column
<!-- Answer -->
Superset 2.1.0 and 3.0.0 both rely on the database connector and engine spec to infer column types. If the database reports a NULL or missing type for a column, Superset marks it as UNKNOWN and normally disables time-based features for that column. There is no special logic in 2.1.0 to treat NULL types as temporal—recognition depends on the type string and engine spec mapping. The fact that your 2.1.0 instance works with a NULL timestamp column is likely due to differences in the metadata returned by the database or connector, or possibly looser validation in dependencies like SQLAlchemy at that time. In 3.0.0, stricter validation or changes in dependencies mean that ambiguous or NULL types are no longer tolerated, so the column is marked as UNKNOWN and can't be used for time filters or charts. The core logic for type inference hasn't changed between these versions; the difference is likely environmental or due to dependency updates, not a deliberate change in Superset itself.
[Reference: Superset 2.1.0 column type inference and engine spec logic](https://github.com/apache/superset/blob/829e4d92d91ceae4b43b1ed3b063ffe45377799c/superset/connectors/sqla/utils.py)
<!-- Dosu Comment Footer -->
*To reply, just mention [@dosu](https://go.dosu.dev/dosubot?utm_source=github&utm_medium=bot-comment&utm_campaign=github-comment-footer-20260415&utm_content=reply-with-mention&utm_term=apache%2Fsuperset).*
---
Docs are dead. Just use [Dosu](https://dosu.dev?utm_source=github&utm_medium=bot-comment&utm_campaign=github-comment-footer-20260415&utm_content=static-docs-tagline&utm_term=apache%2Fsuperset).
[](https://app.dosu.dev/response-feedback?utm_source=github&utm_medium=bot-comment&utm_campaign=github-comment-footer-20260415&utm_content=static-docs-feedback&utm_term=apache%2Fsuperset&message_id=ada30563-213a-4ed8-9bab-097c4d070b4d) [](https://github.dosu.com/apache/superset?utm_source=github&utm_medium=bot-comment&utm_campaign=github-comment-footer-20260415&utm_content=static-docs-ask-repo&utm_term=apache%2Fsuperset) [](https://app.dosu.dev/signup?referrer=openSource&source=github-footer&utm_source=github&utm_medium=bot-comment&utm_campaign=github-comment-footer-20260415&utm_content=static-docs-share-team&utm_term=apache%2Fsuperset)
GitHub link: https://github.com/apache/superset/discussions/35188#discussioncomment-14444036
----
This is an automatically sent email for notifications@superset.apache.org.
To unsubscribe, please send an email to: notifications-unsubscribe@superset.apache.org
---------------------------------------------------------------------
To unsubscribe, e-mail: notifications-unsubscribe@superset.apache.org
For additional commands, e-mail: notifications-help@superset.apache.org