thevar1able/ClickHouse
1
0
Fork 0
mirror of https://github.com/ClickHouse/ClickHouse.git synced 2024-11-23 08:02:02 +00:00
Code Issues Packages Projects Releases Wiki Activity

reorder

Browse Source
This commit is contained in:
DanRoscigno 2023-05-17 14:48:16 -04:00
parent 64bf477ff2
commit a1fc96953f
1 changed files with 19 additions and 18 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

37
docs/en/operations/named-collections.md
View File

@ -13,7 +13,23 @@ Named collections can be configured with DDL or in configuration files and are a
when ClickHouse starts. They simplify the creation of objects and the hiding of credentials
from users without administrative access.
## Storing details for connecting to external sources in the system database
The keys in a named collection must match the parameter names of the corresponding
function, table engine, database, etc. In the examples below the parameter list is
linked to for each type.
Parameters set in a named collection can be overridden in SQL, this is shown in the examples
below.
## Storing named collections in the system database
### DDL example
```sql
CREATE NAMED COLLECTION name AS
key_1 = 'value',
key_2 = 'value2',
url = 'https://connection.url/'
```
### Permissions to create named collections with DDL
@ -37,22 +53,7 @@ To manage named collections with DDL a user must have the `named_control_collect
In the above example the `passowrd_sha256_hex` value is the hexadecimal representation of the SHA256 hash of the password. This configuration for the user `default` has the attribute `replace=true` as in the default configuration has a plain text `password` set, and it is not possible to have both plaintext and sha256 hex passwords set for a user.
:::
## Storing details for connecting to external sources in configuration files
Parameters can be set in XML `<format>CSV</format>` and overridden in SQL `, format = 'TSV'`.
The parameters in SQL can be overridden using format `key` = `value`: `compression_method = 'gzip'`.
Named collections are stored in the system table `system.named_collections` or in `config.xml` file of the ClickHouse server in the `<named_collections>` section and are applied when ClickHouse starts.
### DDL example
```sql
CREATE NAMED COLLECTION name AS
key_1 = 'value',
key_2 = 'value2',
url = 'https://connection.url/'
```
## Storing named collections in configuration files
### XML example
@ -98,7 +99,7 @@ url = 'https://s3.us-east-1.amazonaws.com/yourbucket/mydata/'
</clickhouse>
```
### s3() function and S3 Table Named collection examples
### s3() function and S3 Table named collection examples
Both of the following examples use the same named collection `s3_mydata`: