thevar1able/ClickHouse
1
0
Fork 0
mirror of https://github.com/ClickHouse/ClickHouse.git synced 2024-11-22 07:31:57 +00:00
Code Issues Packages Projects Releases Wiki Activity

update doc

Browse Source
This commit is contained in:
lgbo-ustc 2024-05-14 11:47:50 +08:00
parent e52828abf9
commit fa234cadcb
1 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
docs/en/sql-reference/window-functions/index.md
View File

@ -23,7 +23,7 @@ ClickHouse supports the standard grammar for defining windows and window functio
| `GROUPS` frame | ❌ |
| Calculating aggregate functions over a frame (`sum(value) over (order by time)`) | ✅ (All aggregate functions are supported) |
| `rank()`, `dense_rank()`, `row_number()` | ✅ |
| `percent_rank()` | ✅ equal to `ifNull((rank() OVER(PARTITION BY x order by y) - 1) / nullif(count(1) OVER(PARTITION BY x) -1, 0), 0)`, but more efficient|
| `percent_rank()` | ✅ Efficiently computes the relative standing of a value within a partition in a dataset. This function effectively replaces the more verbose and computationally intensive manual SQL calculation expressed as `ifNull((rank() OVER(PARTITION BY x ORDER BY y) - 1) / nullif(count(1) OVER(PARTITION BY x) - 1, 0), 0)`|
| `lag/lead(value, offset)` | ❌ <br/> You can use one of the following workarounds:<br/> 1) `any(value) over (.... rows between <offset> preceding and <offset> preceding)`, or `following` for `lead` <br/> 2) `lagInFrame/leadInFrame`, which are analogous, but respect the window frame. To get behavior identical to `lag/lead`, use `rows between unbounded preceding and unbounded following` |
| ntile(buckets) | ✅ <br/> Specify window like, (partition by x order by y rows between unbounded preceding and unrounded following). |