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Remove trailing whitespaces from docs/en/sql-reference/statements/select/join.md

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vdimir 2022-07-15 15:03:32 +00:00
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10
docs/en/sql-reference/statements/select/join.md
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@ -36,7 +36,7 @@ Additional join types available in ClickHouse:
- `LEFT ANY JOIN`, `RIGHT ANY JOIN` and `INNER ANY JOIN`, partially (for opposite side of `LEFT` and `RIGHT`) or completely (for `INNER` and `FULL`) disables the cartesian product for standard `JOIN` types.
- `ASOF JOIN` and `LEFT ASOF JOIN`, joining sequences with a non-exact match. `ASOF JOIN` usage is described below.
:::note
:::note
When [join_algorithm](../../../operations/settings/settings.md#settings-join_algorithm) is set to `partial_merge`, `RIGHT JOIN` and `FULL JOIN` are supported only with `ALL` strictness (`SEMI`, `ANTI`, `ANY`, and `ASOF` are not supported).
:::
@ -64,7 +64,7 @@ Rows are joined if the whole complex condition is met. If the conditions are not
The `OR` operator inside the `ON` clause works using the hash join algorithm — for each `OR` argument with join keys for `JOIN`, a separate hash table is created, so memory consumption and query execution time grow linearly with an increase in the number of expressions `OR` of the `ON` clause.
:::note
:::note
If a condition refers columns from different tables, then only the equality operator (`=`) is supported so far.
:::
@ -83,7 +83,7 @@ Consider `table_1` and `table_2`:
Query with one join key condition and an additional condition for `table_2`:
``` sql
SELECT name, text FROM table_1 LEFT OUTER JOIN table_2
SELECT name, text FROM table_1 LEFT OUTER JOIN table_2
ON table_1.Id = table_2.Id AND startsWith(table_2.text, 'Text');
```
@ -100,7 +100,7 @@ Note that the result contains the row with the name `C` and the empty text colum
Query with `INNER` type of a join and multiple conditions:
``` sql
SELECT name, text, scores FROM table_1 INNER JOIN table_2
SELECT name, text, scores FROM table_1 INNER JOIN table_2
ON table_1.Id = table_2.Id AND table_2.scores > 10 AND startsWith(table_2.text, 'Text');
```
@ -199,7 +199,7 @@ For example, consider the following tables:
`ASOF JOIN` can take the timestamp of a user event from `table_1` and find an event in `table_2` where the timestamp is closest to the timestamp of the event from `table_1` corresponding to the closest match condition. Equal timestamp values are the closest if available. Here, the `user_id` column can be used for joining on equality and the `ev_time` column can be used for joining on the closest match. In our example, `event_1_1` can be joined with `event_2_1` and `event_1_2` can be joined with `event_2_3`, but `event_2_2` can’t be joined.
:::note
:::note
`ASOF` join is **not** supported in the [Join](../../../engines/table-engines/special/join.md) table engine.
:::