CLICKHOUSEDOCS-272: More info.

docs/en/getting_started/install.md

@@ -14,7 +14,7 @@ To run ClickHouse on processors that do not support SSE 4.2 or have AArch64 or P
 
 ## Available Installation Options
 
-### From DEB Packages
+### From DEB Packages {#install-from-deb-packages}
 
 It is recommended to use official pre-compiled `deb` packages for Debian or Ubuntu.
 
@@ -39,12 +39,10 @@ You can also download and install packages manually from here: <https://repo.yan
 
 #### Packages
 
-- clickhouse-client
-- clickhouse-server
-- clickhouse-common
-- clickhouse-common-static-dbg
-- clickhouse-tests
-
+- `clickhouse-common-static` — Installs ClickHouse compiled binary files.
+- `clickhouse-server` — Creates symbolic link for `clickhouse-server`. Installs server configuration.
+- `clickhouse-client` — Creates symbolic link for `clickhouse-client `. Installs client configurations.
+- `clickhouse-common-static-dbg` — Installs ClickHouse compiled binary files with debug info.
 
 ### From RPM Packages
 

docs/en/getting_started/tutorial.md

@@ -6,7 +6,7 @@ By going through this tutorial you'll learn how to set up basic ClickHouse clust
 
 ## Single Node Setup
 
-To postpone complexities of distributed environment, we'll start with deploying ClickHouse on a single server or virtual machine. ClickHouse is usually installed from [deb](index.md#from-deb-packages) or [rpm](index.md#from-rpm-packages) packages, but there are [alternatives](index.md#from-docker-image) for the operating systems that do no support them.
+To postpone complexities of distributed environment, we'll start with deploying ClickHouse on a single server or virtual machine. ClickHouse is usually installed from [deb](index.md#install-from-deb-packages) or [rpm](index.md#from-rpm-packages) packages, but there are [alternatives](index.md#from-docker-image) for the operating systems that do no support them.
 
 For example, you have chosen `deb` packages and executed:
 ``` bash

docs/en/operations/performance/sampling_query_profiler.md

@@ -4,9 +4,9 @@ ClickHouse runs sampling profiler that allows to analyse query execution. Using
 
 To use profiler:
 
-- Setup the [trace_log][../server_settings/settings.md#server_settings-trace_log] section of the server configuration.
+- Setup the [trace_log](../server_settings/settings.md#server_settings-trace_log) section of the server configuration.
 
-    This section configures the [trace_log][../system_tables.md#system_tables-trace_log] system table containing the results of the profiler functioning. It is configured by default.
+    This section configures the [trace_log](../system_tables.md#system_tables-trace_log) system table containing the results of the profiler functioning. It is configured by default.
 
 - Setup the [query_profiler_cpu_time_period_ns](../settings/settings.md#query_profiler_cpu_time_period_ns) and [query_profiler_real_time_period_ns](../settings/settings.md#query_profiler_real_time_period_ns) settings.
 
@@ -16,7 +16,7 @@ Default sampling frequency is one sample per second. This frequency allows to ca
 
 To analyze the `trace_log` system table:
 
-- Install the `clickhouse-common-static-dbg` package.
+- Install the `clickhouse-common-static-dbg` package. See [Install from DEB Packages](../../getting_started/install.md#install-from-deb-packages).
 - Allow introspection functions.
 
     For security reasons introspection functions are disabled by default.

docs/en/operations/server_settings/settings.md

@@ -16,33 +16,40 @@ Default value: 3600.
 ```
 
 
-## compression
+## compression {#server-settings-compression}
 
-Data compression settings.
+Data compression settings for [MergeTree](../table_engines/mergetree.md)-engine tables.
 
 !!! warning
     Don't use it if you have just started using ClickHouse.
 
-The configuration looks like this:
+Configuration template:
 
 ```xml
 <compression>
     <case>
-      <parameters/>
+      <min_part_size>...</min_part_size>
+      <min_part_size_ratio>...</min_part_size_ratio>
+      <method>...</method>
     </case>
     ...
 </compression>
 ```
 
-You can configure multiple sections `<case>`.
+`<case>` fields:
 
-Block field `<case>`:
+- `min_part_size` – The minimum size of a data part.
+- `min_part_size_ratio` – The ratio of the data part size to the table size.
+- `method` – Compression method. Acceptable values: `lz4` or `zstd`.
 
-- ``min_part_size`` – The minimum size of a table part.
-- ``min_part_size_ratio`` – The ratio of the minimum size of a table part to the full size of the table.
-- ``method`` – Compression method. Acceptable values ​: ``lz4`` or ``zstd``(experimental).
+You can configure multiple `<case>` sections.
 
-ClickHouse checks `min_part_size` and `min_part_size_ratio` and processes the `case` blocks that match these conditions. If none of the `<case>` matches, ClickHouse applies the `lz4` compression algorithm.
+Actions when conditions are met:
+
+- If a data part matches a condition set, ClickHouse uses the specified compression method.
+- If a data part matches multiple condition sets, ClickHouse uses the first matched condition set.
+
+If no conditions met for a data part, ClickHouse uses the `lz4` compression.
 
 **Example**
 

docs/en/operations/table_engines/jdbc.md

@@ -54,18 +54,12 @@ mysql> select * from test;
 Creating a table in ClickHouse server and selecting data from it:
 
 ```sql
-CREATE TABLE jdbc_table ENGINE JDBC('jdbc:mysql://localhost:3306/?user=root&password=root', 'test', 'test')
-```
-```sql
-DESCRIBE TABLE jdbc_table
-```
-```text
-┌─name───────────────┬─type───────────────┬─default_type─┬─default_expression─┐
-│ int_id             │ Int32              │              │                    │
-│ int_nullable       │ Nullable(Int32)    │              │                    │
-│ float              │ Float32            │              │                    │
-│ float_nullable     │ Nullable(Float32)  │              │                    │
-└────────────────────┴────────────────────┴──────────────┴────────────────────┘
+CREATE TABLE jdbc_table(
+    `int_id` Int32,
+    `int_nullable` Nullable(Int32),
+    `float` Float32,
+    `float_nullable` Nullable(Float32)
+)ENGINE JDBC('jdbc:mysql://localhost:3306/?user=root&password=root', 'test', 'test')
 ```
 ```sql
 SELECT *

docs/en/query_language/create.md

@@ -129,7 +129,7 @@ Defines storage time for values. Can be specified only for MergeTree-family tabl
 
 ### Column Compression Codecs {#codecs}
 
-By default, ClickHouse applies the compression method, defined in [server settings](../operations/server_settings/settings.md#compression), to columns. You can also define the compression method for each individual column in the `CREATE TABLE` query.
+By default, ClickHouse applies the `lz4` compression method. For `MergeTree`-engine family you can change the default compression method in the [compression](../operations/server_settings/settings.md#server-settings-compression) section of a server configuration. You can also define the compression method for each individual column in the `CREATE TABLE` query.
 
 ```sql
 CREATE TABLE codec_example
@@ -151,10 +151,10 @@ If a codec is specified, the default codec doesn't apply. Codecs can be combined
 
 Compression is supported for the following table engines:
 
-- [MergeTree](../operations/table_engines/mergetree.md) family
-- [Log](../operations/table_engines/log_family.md) family
-- [Set](../operations/table_engines/set.md)
-- [Join](../operations/table_engines/join.md)
+- [MergeTree](../operations/table_engines/mergetree.md) family. Supports column compression codecs and selecting the default compression method by [compression](../operations/server_settings/settings.md#server-settings-compression) settings.
+- [Log](../operations/table_engines/log_family.md) family. Uses the `lz4` compression method by default and supports column compression codecs.
+- [Set](../operations/table_engines/set.md). Only supported the default compression.
+- [Join](../operations/table_engines/join.md). Only supported the default compression.
 
 ClickHouse supports common purpose codecs and specialized codecs.
 

docs/ru/getting_started/install.md

@@ -14,7 +14,7 @@ $ grep -q sse4_2 /proc/cpuinfo && echo "SSE 4.2 supported" || echo "SSE 4.2 not
 
 ## Доступные варианты установки
 
-### Из DEB пакетов {#from-deb-packages}
+### Из DEB пакетов {#install-from-deb-packages}
 
 Яндекс рекомендует использовать официальные скомпилированные `deb` пакеты для Debian или Ubuntu.