Fix mat view guide typos (#189)

Co-authored-by: Nick Woolmer <29717167+nwoolmer@users.noreply.github.com>

Author: puzpuzpuz

documentation/guides/mat-views.md

@@ -106,18 +106,16 @@ If you are unfamiliar with the OHLC concept, please see our
 
 ```questdb-sql title="trades_OHLC_15m DDL"
 CREATE MATERIALIZED VIEW 'trades_OHLC_15m'
-WITH BASE 'trades' REFRESH INCREMENTAL
-AS (
-  SELECT
-      timestamp, symbol,
-      first(price) AS open,
-      max(price) as high,
-      min(price) as low,
-      last(price) AS close,
-      sum(amount) AS volume
-  FROM trades
-  SAMPLE BY 15m
-) PARTITION BY MONTH;
+WITH BASE 'trades' REFRESH INCREMENTAL AS
+SELECT
+    timestamp, symbol,
+    first(price) AS open,
+    max(price) as high,
+    min(price) as low,
+    last(price) AS close,
+    sum(amount) AS volume
+FROM trades
+SAMPLE BY 15m;
 ```
 
 In this example:
@@ -132,12 +130,13 @@ In this example:
 4. The `SAMPLE BY` query contains two key column (`timestamp`, `symbol`) and
    five aggregates (`first`, `max`, `min`, `last`, `price`) calculated in `15m`
    time buckets.
-5. The view is partitioned by `DAY`.
+5. The view is partitioned by `MONTH`. This partitioning is selected
+   [by default](#default-partitioning) based on the `SAMPLE BY` interval.
 6. No TTL is defined
    - Therefore, the materialized view will contain a summary of _all_ the base
      `trades` table's data.
 
-Many parts of the above DDL statement are optional and can be ommited:
+Many parts of the above DDL statement are optional and can be omitted:
 
 ```questdb-sql title="trades_OHLC_15m compact DDL"
 CREATE MATERIALIZED VIEW 'trades_OHLC_15m' AS
@@ -357,20 +356,12 @@ useful.
 
 ## Limitations
 
-### Beta
-
 - Not all `SAMPLE BY` syntax is supported, for example, `FILL`.
 - The `INCREMENTAL` refresh strategy relies on deduplicated inserts (O3 writes)
-  - We will instead delete a time range and insert the data as an append, which
-    is **much** faster.
-  - This also means that currently, deduplication keys must be aligned across
+  - This means that currently, deduplication keys must be aligned across
     the `base` table and the view.
-
-### Post-release
-
 - Only `INCREMENTAL` refresh is supported
-  - We intend to add alternatives, such as:
-    - `PERIODIC` (once per partition),
+  - In next versions, we intend to add alternatives, such as:
     - `TIMER` (once per time interval)
     - `MANUAL` (only when manually triggered)
 - `INCREMENTAL` refresh is only triggered by inserts into the `base` table, not
@@ -496,7 +487,6 @@ Instead of storing the raw data, we will store one row, per symbol, per side,
 per day of data.
 
 ```questdb-sql title="down-sampling test query" demo
-
 SELECT timestamp, symbol, side, price, amount, "latest" as timestamp FROM (
     SELECT timestamp,
            symbol,