Apache Zookeeper
What is Zookeeper ?¶
ZooKeeper is a centralized service for maintaining configuration information, naming, providing distributed synchronization, and providing group services. All of these kinds of services are used in some form or another by distributed applications. Each time they are implemented there is a lot of work that goes into fixing the bugs and race conditions that are inevitable.
Environment¶
Note
If you need to use this data source, you need to upgrade the DataCap service to >= 1.5.x
Support Time: 2023-02-07
SQL statement syntax¶
This chapter describes the SQL syntax used in Zookeeper on DataCap.
SELECT¶
Synopsis
SELECT [ * | <Columns> ] select_expression [, ...]
FROM from_item [. ...]
where from_item
is one of
table_name [ `a.b` | a.b | `a`.`b`]
Danger
When table_name
is set to all
the root directory is searched.
Select expressions
Each select_expression
must be in one of the following forms:
expression [ column_alias ]
*
In the case of expression [ column_alias ]
, a single output column is defined.
In the case of *
, all columns of the relation defined by the query are included in the result set.
*
--------
data
Danger
If it is a multi-level directory, such as /zookeeper/id/2
, it will be written `zookeeper`.`id`.`2`, and use .
to split between directories.
Configure¶
DataCap uses configuration files by default zookeeper.json
Note
If your Zookeeper service version requires other special configurations, please refer to modifying the configuration file and restarting the DataCap service.
Field | Required | Default Value |
---|---|---|
Name |
:material-check-circle: | - |
Host |
:material-check-circle: | 127.0.0.1:2181 |
Port |
:material-close-circle: | 1 |
Version (Validation)¶
Warning
The online service has not been tested yet, if you have detailed test results, please submit issues to us
-
3.1.x
-3.7.x
创建日期: February 8, 2023