Adding examples to live view docs.

docs/en/sql-reference/statements/create/view.md

@@ -41,7 +41,6 @@ SELECT a, b, c FROM (SELECT ...)
 CREATE MATERIALIZED VIEW [IF NOT EXISTS] [db.]table_name [ON CLUSTER] [TO[db.]name] [ENGINE = engine] [POPULATE] AS SELECT ...
 ```
 
-
 Materialized views store data transformed by the corresponding [SELECT](../../../sql-reference/statements/select/index.md) query.
 
 When creating a materialized view without `TO [db].[table]`, you must specify `ENGINE` – the table engine for storing data.
@@ -95,12 +94,63 @@ You can watch for changes in the live view query result using the [WATCH](../../
 WATCH [db.]live_view
 ```
 
+**Example:**
+
+```sql
+CREATE TABLE mt (x Int8) Engine = MergeTree ORDER BY x;
+CREATE LIVE VIEW lv AS SELECT sum(x) FROM mt;
+```
+
+Watch a live view while doing a parallel insert into the source table.
+
+```sql
+WATCH lv
+```
+
+```bash
+┌─sum(x)─┬─_version─┐
+│      1 │        1 │
+└────────┴──────────┘
+┌─sum(x)─┬─_version─┐
+│      2 │        2 │
+└────────┴──────────┘
+┌─sum(x)─┬─_version─┐
+│      6 │        3 │
+└────────┴──────────┘
+...
+```
+
+```sql
+INSERT INTO mt VALUES (1);
+INSERT INTO mt VALUES (2);
+INSERT INTO mt VALUES (3);
+```
+
 or add [EVENTS](../../../sql-reference/statements/watch.md#events-clause) clause to just get change events.
 
 ```sql
 WATCH [db.]live_view EVENTS
 ```
 
+**Example:**
+
+```sql
+WATCH lv EVENTS
+```
+
+```bash
+┌─version─┐
+│       1 │
+└─────────┘
+┌─version─┐
+│       2 │
+└─────────┘
+┌─version─┐
+│       3 │
+└─────────┘
+...
+```
+
 You can execute [SELECT](../../../sql-reference/statements/select/index.md) query on a live view in the same way as for any regular view or a table. If the query result is cached it will return the result immediately without running the stored query on the underlying tables.
 
 ```sql
@@ -121,6 +171,13 @@ CREATE LIVE VIEW [db.]table_name WITH TIMEOUT [value_in_sec] AS SELECT ...
 
 If the timeout value is not specified then the value specified by the `temporary_live_view_timeout` setting is used.
 
+**Example:**
+
+```sql
+CREATE TABLE mt (x Int8) Engine = MergeTree ORDER BY x;
+CREATE LIVE VIEW lv WITH TIMEOUT 15 AS SELECT sum(x) FROM mt;
+```
+
 ### With Refresh {#live-view-with-refresh}
 
 When a live view is created with a `WITH REFRESH` clause then it will be automatically refreshed after the specified number of seconds elapse since the last refresh or trigger.
@@ -131,11 +188,47 @@ CREATE LIVE VIEW [db.]table_name WITH REFRESH [value_in_sec] AS SELECT ...
 
 If the refresh value is not specified then the value specified by the `periodic_live_view_refresh` setting is used.
 
+**Example:**
+
+```sql
+CREATE LIVE VIEW lv WITH REFRESH 5 AS SELECT now();
+WATCH lv
+```
+
+```bash
+┌───────────────now()─┬─_version─┐
+│ 2021-02-21 08:47:05 │        1 │
+└─────────────────────┴──────────┘
+┌───────────────now()─┬─_version─┐
+│ 2021-02-21 08:47:10 │        2 │
+└─────────────────────┴──────────┘
+┌───────────────now()─┬─_version─┐
+│ 2021-02-21 08:47:15 │        3 │
+└─────────────────────┴──────────┘
+```
+
 You can combine `WITH TIMEOUT` and `WITH REFRESH` clauses using an `AND` clause. 
 
 ```sql
 CREATE LIVE VIEW [db.]table_name WITH TIMEOUT [value_in_sec] AND REFRESH [value_in_sec] AS SELECT ...
 ```
+
+**Example:**
+
+```sql
+CREATE LIVE VIEW lv WITH TIMEOUT 15 AND REFRESH 5 AS SELECT now();
+```
+
+After 15 sec the live view will be automatically dropped if there are no active `WATCH` queries.
+
+```sql
+WATCH lv
+```
+
+```
+Code: 60. DB::Exception: Received from localhost:9000. DB::Exception: Table default.lv doesn't exist.. 
+```
+
 ### Usage
 
 Most common uses of live view tables include:

docs/en/sql-reference/statements/watch.md

@@ -25,6 +25,26 @@ WATCH [db.]live_view
 
 The virtual `_version` column in the query result indicates the current result version.
 
+**Example:**
+
+```sql
+CREATE LIVE VIEW lv WITH REFRESH 5 AS SELECT now();
+WATCH lv
+```
+
+```bash
+┌───────────────now()─┬─_version─┐
+│ 2021-02-21 09:17:21 │        1 │
+└─────────────────────┴──────────┘
+┌───────────────now()─┬─_version─┐
+│ 2021-02-21 09:17:26 │        2 │
+└─────────────────────┴──────────┘
+┌───────────────now()─┬─_version─┐
+│ 2021-02-21 09:17:31 │        3 │
+└─────────────────────┴──────────┘
+...
+```
+
 By default, the requested data is returned to the client, while in conjunction with [INSERT INTO](../../sql-reference/statements/insert-into.md) it can be forwarded to a different table.
 
 ```sql
@@ -36,7 +56,24 @@ INSERT INTO [db.]table WATCH [db.]live_view ...
 The `EVENTS` clause can be used to obtain a short form of the `WATCH` query where instead of the query result you will just get the latest query result version.
 
 ```sql
-WATCH [db.]live_view EVENTS LIMIT 1
+WATCH [db.]live_view EVENTS
+```
+
+**Example:**
+
+```sql
+CREATE LIVE VIEW lv WITH REFRESH 5 AS SELECT now();
+WATCH lv EVENTS
+```
+
+```bash
+┌─version─┐
+│       1 │
+└─────────┘
+┌─version─┐
+│       2 │
+└─────────┘
+...
 ```
 
 ## LIMIT Clause {#limit-clause}
@@ -44,7 +81,20 @@ WATCH [db.]live_view EVENTS LIMIT 1
 The `LIMIT n` clause species the number of updates the `WATCH` query should wait for before terminating. By default there is no limit on the number of updates and therefore the query will not terminate. The value of `0` indicates that the `WATCH` query should not wait for any new query results and therefore will return immediately once query is evaluated.
 
 ```sql
-WATCH [db.]live_view LIMIT 2
+WATCH [db.]live_view LIMIT 1
+```
+
+**Example:**
+
+```sql
+CREATE LIVE VIEW lv WITH REFRESH 5 AS SELECT now();
+WATCH lv EVENTS LIMIT 1
+```
+
+```bash
+┌─version─┐
+│       1 │
+└─────────┘
 ```
 
 ## FORMAT Clause {#format-clause}