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Raw Queries and Responses

1. Shard Calculation

Query:

Response:

Calculated Shard: 174 (from laksa157)

2. Crawled Status Check

Query:

curl -X POST \
  'http://laksa174.int.ahrefs:8124/' \
  -H 'Content-Type: text/plain' \
  -H 'X-ClickHouse-Database: crawler3' \
  -H 'Authorization: Basic YXBpOg==' \
  -d 'SELECT getAhrefsURLFromUnparsed(src_unparsed) AS found_url, ifNull(toUnixTimestamp(download_stamp), 0) AS crawl_time, ifNull(toUnixTimestamp(props_url_first_seen), 0) AS first_indexed_time, download_http_code AS http_code, src_unparsed AS src_unparsed, src_root_hash AS src_root_hash, history_drop_reason AS history_drop_reason, meta_title AS meta_title, meta_descriptions AS meta_descriptions, attrs_boilerpipe_text AS attrs_boilerpipe_text, attrs_markdown AS attrs_markdown, attrs_readable_markdown AS attrs_readable_markdown, meta_canonical AS meta_canonical FROM crawler3.page_info_local FINAL PREWHERE (src_root_hash, src_unparsed) IN ((getAhrefsRootHashFromUnparsed(getAhrefsUnparsedNoserviceFromURL(\'https://github.com/ClickHouse/ClickHouse/issues/61313\')), getAhrefsUnparsedNoserviceFromURL(\'https://github.com/ClickHouse/ClickHouse/issues/61313\'))) FORMAT JSONEachRow'

Response:

{"found_url":"https:\/\/github.com\/ClickHouse\/ClickHouse\/issues\/61313","crawl_time":1755687060,"first_indexed_time":0,"http_code":200,"src_unparsed":"com,github!\/ClickHouse\/ClickHouse\/issues\/61313 s443","src_root_hash":"6325672905007345774","history_drop_reason":null,"meta_title":"group by count with null values in the grouping key returns hard to understand result · Issue #61313 · ClickHouse\/ClickHouse · GitHub","meta_descriptions":["Describe the unexpected behaviour I'm having trouble understanding how nulls are handled when used as grouping keys. I can't tell if there's something I'm missing here, or if this is a bug in ClickHouse. How to reproduce ClickHouse serve..."],"attrs_boilerpipe_text":"Describe the unexpected behaviour I'm having trouble understanding how nulls are handled when used as grouping keys. I can't tell if there's something I'm missing here, or if this is a bug in ClickHouse. How to reproduce ClickHouse server version: bce519d15486 :) select version();\n\nSELECT version()\n\nQuery id: ef482266-bbdb-4b62-ad14-3838c14c66cb\n\n┌─version()──┐\n│ 23.12.4.15 │\n└────────────┘\n\n1 row in set. Elapsed: 0.001 sec.\n Example: bce519d15486 :) CREATE OR REPLACE TABLE ibis_testing.topk (x Nullable(Int64)) ENGINE = Memory;\n\nCREATE OR REPLACE TABLE ibis_testing.topk\n(\n    `x` Nullable(Int64)\n)\nENGINE = Memory\n\nQuery id: 76f08dbb-380e-4336-b156-f71b992ca09e\n\nOk.\n\n0 rows in set. Elapsed: 0.006 sec.\n\nbce519d15486 :) INSERT INTO ibis_testing.topk VALUES (1), (1), (NULL);\n\nINSERT INTO ibis_testing.topk FORMAT Values\n\nQuery id: fec175db-566c-4019-8752-b36dcfc95f2c\n\nOk.\n\n3 rows in set. Elapsed: 0.002 sec.\n\nbce519d15486 :) select x, count(*), count(1), count(), countIf(x is null) from topk group by x;\n\nSELECT\n    x,\n    count(*),\n    count(1),\n    count(),\n    countIf(x IS NULL)\nFROM topk\nGROUP BY x\n\nQuery id: df3b4079-c6df-455f-ad2b-259612b42df6\n\n┌────x─┬─count()─┬─count()─┬─count()─┬─countIf(isNull(x))─┐\n│ ᴺᵁᴸᴸ │       0 │       0 │       0 │                  0 │\n│    1 │       3 │       3 │       3 │                  1 │\n└──────┴─────────┴─────────┴─────────┴────────────────────┘\n\n2 rows in set. Elapsed: 0.002 sec.\n Expected behavior I would expect the  count()  aggregations to return 1 for  NULL  and  2  for  1 , and the  countIf  aggregation to return  1  for  NULL  and  0  for  1 .","attrs_markdown":"[Skip to content](https:\/\/github.com\/ClickHouse\/ClickHouse\/issues\/61313#start-of-content)\n\n## Navigation Menu\nToggle navigation\n\n[Sign in](https:\/\/github.com\/login?return_to=https%3A%2F%2Fgithub.com%2FClickHouse%2FClickHouse%2Fissues%2F61313)\n\nAppearance settings\n\n- Product\n  - [GitHub Copilot Write better code with AI](https:\/\/github.com\/features\/copilot)\n  - [GitHub Spark New Build and deploy intelligent apps](https:\/\/github.com\/features\/spark)\n  - [GitHub Models New Manage and compare prompts](https:\/\/github.com\/features\/models)\n  - [GitHub Advanced Security Find and fix vulnerabilities](https:\/\/github.com\/security\/advanced-security)\n  - [Actions Automate any workflow](https:\/\/github.com\/features\/actions)\n  \n  - [Codespaces Instant dev environments](https:\/\/github.com\/features\/codespaces)\n  - 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I can't tell if there's something I'm missing here, or if this is a bug in ClickHouse.\n\n**How to reproduce**\n\nClickHouse server version:\n```\nbce519d15486 :) select version();\n\nSELECT version()\n\nQuery id: ef482266-bbdb-4b62-ad14-3838c14c66cb\n\n┌─version()──┐\n│ 23.12.4.15 │\n└────────────┘\n\n1 row in set. Elapsed: 0.001 sec.\n```\nExample:\n```\nbce519d15486 :) CREATE OR REPLACE TABLE ibis_testing.topk (x Nullable(Int64)) ENGINE = Memory;\n\nCREATE OR REPLACE TABLE ibis_testing.topk\n(\n    `x` Nullable(Int64)\n)\nENGINE = Memory\n\nQuery id: 76f08dbb-380e-4336-b156-f71b992ca09e\n\nOk.\n\n0 rows in set. Elapsed: 0.006 sec.\n\nbce519d15486 :) INSERT INTO ibis_testing.topk VALUES (1), (1), (NULL);\n\nINSERT INTO ibis_testing.topk FORMAT Values\n\nQuery id: fec175db-566c-4019-8752-b36dcfc95f2c\n\nOk.\n\n3 rows in set. Elapsed: 0.002 sec.\n\nbce519d15486 :) select x, count(*), count(1), count(), countIf(x is null) from topk group by x;\n\nSELECT\n    x,\n    count(*),\n    count(1),\n    count(),\n    countIf(x IS NULL)\nFROM topk\nGROUP BY x\n\nQuery id: df3b4079-c6df-455f-ad2b-259612b42df6\n\n┌────x─┬─count()─┬─count()─┬─count()─┬─countIf(isNull(x))─┐\n│ ᴺᵁᴸᴸ │       0 │       0 │       0 │                  0 │\n│    1 │       3 │       3 │       3 │                  1 │\n└──────┴─────────┴─────────┴─────────┴────────────────────┘\n\n2 rows in set. Elapsed: 0.002 sec.\n```\n**Expected behavior**\n\nI would expect the `count()` aggregations to return 1 for `NULL` and `2` for `1`, and the `countIf` aggregation to return `1` for `NULL` and `0` for `1`.\n\n## Metadata\n## Metadata\n### Assignees\n- [![@CurtizJ](https:\/\/avatars.githubusercontent.com\/u\/20361854?s=64&v=4)CurtizJ](https:\/\/github.com\/CurtizJ)\n\n### Labels\n[bugConfirmed user-visible misbehaviour in official release](https:\/\/github.com\/ClickHouse\/ClickHouse\/issues?q=state%3Aopen%20label%3A%22bug%22)Confirmed user-visible misbehaviour in official release\n\n### Type\nNo type\n\n### Projects\nNo projects\n\n### Milestone\nNo milestone\n\n### Relationships\nNone yet\n\n### Development\nNo branches or pull requests\n## Issue actions\n\n## Footer\n© 2025 GitHub, Inc.\n\n### Footer navigation\n- [Terms](https:\/\/docs.github.com\/site-policy\/github-terms\/github-terms-of-service)\n- [Privacy](https:\/\/docs.github.com\/site-policy\/privacy-policies\/github-privacy-statement)\n- [Security](https:\/\/github.com\/security)\n- [Status](https:\/\/www.githubstatus.com\/)\n- [Docs](https:\/\/docs.github.com\/)\n- [Contact](https:\/\/support.github.com\/?tags=dotcom-footer)\n- Manage cookies\n- Do not share my personal information\n\nYou can’t perform that action at this time.","attrs_readable_markdown":null,"meta_canonical":null}

3. Robots.txt Check

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Response:

4. Spam/Ban Check

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5. Seen Status Check

ℹ️ Skipped - page is already crawled

📄

INDEXABLE

✅

CRAWLED

7 months ago

🤖

ROBOTS ALLOWED

Page Info Filters

Filter	Status	Condition	Details
HTTP status	PASS	`download_http_code = 200`	HTTP 200
Age cutoff	PASS	`download_stamp > now() - 6 MONTH`	7.7 months ago (distributed domain, exempt)
History drop	PASS	`isNull(history_drop_reason)`	No drop reason
Spam/ban	PASS	`fh_dont_index != 1 AND ml_spam_score = 0`	ml_spam_score=0
Canonical	PASS	`meta_canonical IS NULL OR = '' OR = src_unparsed`	Not set

Page Details

Property	Value
URL	https://github.com/ClickHouse/ClickHouse/issues/61313
Last Crawled	2025-08-20 10:51:00 (7 months ago)
First Indexed	not set
HTTP Status Code	200
Meta Title	group by count with null values in the grouping key returns hard to understand result · Issue #61313 · ClickHouse/ClickHouse · GitHub
Meta Description	Describe the unexpected behaviour I'm having trouble understanding how nulls are handled when used as grouping keys. I can't tell if there's something I'm missing here, or if this is a bug in ClickHouse. How to reproduce ClickHouse serve...
Meta Canonical	null
Boilerpipe Text	Describe the unexpected behaviour I'm having trouble understanding how nulls are handled when used as grouping keys. I can't tell if there's something I'm missing here, or if this is a bug in ClickHouse. How to reproduce ClickHouse server version: bce519d15486 :) select version(); SELECT version() Query id: ef482266-bbdb-4b62-ad14-3838c14c66cb ┌─version()──┐ │ 23.12.4.15 │ └────────────┘ 1 row in set. Elapsed: 0.001 sec. Example: bce519d15486 :) CREATE OR REPLACE TABLE ibis_testing.topk (x Nullable(Int64)) ENGINE = Memory; CREATE OR REPLACE TABLE ibis_testing.topk ( `x` Nullable(Int64) ) ENGINE = Memory Query id: 76f08dbb-380e-4336-b156-f71b992ca09e Ok. 0 rows in set. Elapsed: 0.006 sec. bce519d15486 :) INSERT INTO ibis_testing.topk VALUES (1), (1), (NULL); INSERT INTO ibis_testing.topk FORMAT Values Query id: fec175db-566c-4019-8752-b36dcfc95f2c Ok. 3 rows in set. Elapsed: 0.002 sec. bce519d15486 :) select x, count(), count(1), count(), countIf(x is null) from topk group by x; SELECT x, count(), count(1), count(), countIf(x IS NULL) FROM topk GROUP BY x Query id: df3b4079-c6df-455f-ad2b-259612b42df6 ┌────x─┬─count()─┬─count()─┬─count()─┬─countIf(isNull(x))─┐ │ ᴺᵁᴸᴸ │ 0 │ 0 │ 0 │ 0 │ │ 1 │ 3 │ 3 │ 3 │ 1 │ └──────┴─────────┴─────────┴─────────┴────────────────────┘ 2 rows in set. Elapsed: 0.002 sec. Expected behavior I would expect the count() aggregations to return 1 for NULL and 2 for 1 , and the countIf aggregation to return 1 for NULL and 0 for 1 .
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Dismiss alert {{ message }} [ClickHouse](https://github.com/ClickHouse) / [ClickHouse](https://github.com/ClickHouse/ClickHouse) Public - [Notifications](https://github.com/login?return_to=%2FClickHouse%2FClickHouse) You must be signed in to change notification settings - [Fork 7.6k](https://github.com/login?return_to=%2FClickHouse%2FClickHouse) - [Star 42.4k](https://github.com/login?return_to=%2FClickHouse%2FClickHouse) - [Code](https://github.com/ClickHouse/ClickHouse) - [Issues 4.4k](https://github.com/ClickHouse/ClickHouse/issues) - [Pull requests 669](https://github.com/ClickHouse/ClickHouse/pulls) - [Discussions](https://github.com/ClickHouse/ClickHouse/discussions) - [Actions](https://github.com/ClickHouse/ClickHouse/actions) - [Projects 0](https://github.com/ClickHouse/ClickHouse/projects) - [Wiki](https://github.com/ClickHouse/ClickHouse/wiki) - [Security](https://github.com/ClickHouse/ClickHouse/security) [Uh oh\!](https://github.com/ClickHouse/ClickHouse/security) [There was an error while loading.](https://github.com/ClickHouse/ClickHouse/security) [Please reload this page](https://github.com/ClickHouse/ClickHouse/issues/61313). - [Insights](https://github.com/ClickHouse/ClickHouse/pulse) Additional navigation options - [Code](https://github.com/ClickHouse/ClickHouse) - [Issues](https://github.com/ClickHouse/ClickHouse/issues) - [Pull requests](https://github.com/ClickHouse/ClickHouse/pulls) - [Discussions](https://github.com/ClickHouse/ClickHouse/discussions) - [Actions](https://github.com/ClickHouse/ClickHouse/actions) - [Projects](https://github.com/ClickHouse/ClickHouse/projects) - [Wiki](https://github.com/ClickHouse/ClickHouse/wiki) - [Security](https://github.com/ClickHouse/ClickHouse/security) - [Insights](https://github.com/ClickHouse/ClickHouse/pulse) # group by count with null values in the grouping key returns hard to understand result \#61313 [New issue](https://github.com/login?return_to=) Copy link [New issue](https://github.com/login?return_to=) Copy link Closed [\#61393](https://github.com/ClickHouse/ClickHouse/pull/61393) Closed [group by count with null values in the grouping key returns hard to understand result](https://github.com/ClickHouse/ClickHouse/issues/61313#top) \#61313 [\#61393](https://github.com/ClickHouse/ClickHouse/pull/61393) Copy link Assignees [![CurtizJ](https://avatars.githubusercontent.com/u/20361854?s=64&v=4)](https://github.com/CurtizJ) Labels [bugConfirmed user-visible misbehaviour in official release](https://github.com/ClickHouse/ClickHouse/issues?q=state%3Aopen%20label%3A%22bug%22)Confirmed user-visible misbehaviour in official release [![@cpcloud](https://avatars.githubusercontent.com/u/417981?u=b0ceb39e415c82f7739a1f1414a605e3764de52b&v=4&size=80)](https://github.com/cpcloud) ## Description [![@cpcloud](https://avatars.githubusercontent.com/u/417981?u=b0ceb39e415c82f7739a1f1414a605e3764de52b&v=4&size=48)](https://github.com/cpcloud) [cpcloud](https://github.com/cpcloud) opened [on Mar 13, 2024](https://github.com/ClickHouse/ClickHouse/issues/61313#issue-2184239082) Issue body actions Describe the unexpected behaviour I'm having trouble understanding how nulls are handled when used as grouping keys. I can't tell if there's something I'm missing here, or if this is a bug in ClickHouse. How to reproduce ClickHouse server version: ``` bce519d15486 :) select version(); SELECT version() Query id: ef482266-bbdb-4b62-ad14-3838c14c66cb ┌─version()──┐ │ 23.12.4.15 │ └────────────┘ 1 row in set. Elapsed: 0.001 sec. ``` Example: ``` bce519d15486 :) CREATE OR REPLACE TABLE ibis_testing.topk (x Nullable(Int64)) ENGINE = Memory; CREATE OR REPLACE TABLE ibis_testing.topk ( `x` Nullable(Int64) ) ENGINE = Memory Query id: 76f08dbb-380e-4336-b156-f71b992ca09e Ok. 0 rows in set. Elapsed: 0.006 sec. bce519d15486 :) INSERT INTO ibis_testing.topk VALUES (1), (1), (NULL); INSERT INTO ibis_testing.topk FORMAT Values Query id: fec175db-566c-4019-8752-b36dcfc95f2c Ok. 3 rows in set. Elapsed: 0.002 sec. bce519d15486 :) select x, count(), count(1), count(), countIf(x is null) from topk group by x; SELECT x, count(), count(1), count(), countIf(x IS NULL) FROM topk GROUP BY x Query id: df3b4079-c6df-455f-ad2b-259612b42df6 ┌────x─┬─count()─┬─count()─┬─count()─┬─countIf(isNull(x))─┐ │ ᴺᵁᴸᴸ │ 0 │ 0 │ 0 │ 0 │ │ 1 │ 3 │ 3 │ 3 │ 1 │ └──────┴─────────┴─────────┴─────────┴────────────────────┘ 2 rows in set. Elapsed: 0.002 sec. ``` Expected behavior I would expect the `count()` aggregations to return 1 for `NULL` and `2` for `1`, and the `countIf` aggregation to return `1` for `NULL` and `0` for `1`. ## Metadata ## Metadata ### Assignees - [![@CurtizJ](https://avatars.githubusercontent.com/u/20361854?s=64&v=4)CurtizJ](https://github.com/CurtizJ) ### Labels [bugConfirmed user-visible misbehaviour in official release](https://github.com/ClickHouse/ClickHouse/issues?q=state%3Aopen%20label%3A%22bug%22)Confirmed user-visible misbehaviour in official release ### Type No type ### Projects No projects ### Milestone No milestone ### Relationships None yet ### Development No branches or pull requests ## Issue actions ## Footer © 2025 GitHub, Inc. ### Footer navigation - [Terms](https://docs.github.com/site-policy/github-terms/github-terms-of-service) - [Privacy](https://docs.github.com/site-policy/privacy-policies/github-privacy-statement) - [Security](https://github.com/security) - [Status](https://www.githubstatus.com/) - [Docs](https://docs.github.com/) - [Contact](https://support.github.com/?tags=dotcom-footer) - Manage cookies - Do not share my personal information You can’t perform that action at this time.
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