SQL quick reference

CREATE STREAM

Create a new HStreamDB stream with the stream name given. An exception will be thrown if the stream is already created. See CREATE STREAM.

CREATE STREAM stream_name [AS select_query] [WITH (stream_option [, ...])];

CREATE VIEW

Create a new view with the view name given. A view is a physical object like a stream and it is updated with time. An exception will be thrown if the view is already created. The name of a view can either be the same as a stream. See CREATE VIEW.

CREATE VIEW view_name AS select_query;

SELECT (from streams)

Continuously get records from the stream(s) specified as streaming data flows in. It is usually used in an interactive CLI to monitor real-time changes of data. Note that the query writes these records to a random-named stream. See SELECT (Stream).

SELECT <* | expression [ AS field_alias ] [, ...]>
  FROM stream_name [, ...]
  [ WHERE search_condition ]
  [ GROUP BY field_name [, window_type] ]
  EMIT CHANGES;

SELECT (from views)

Get record(s) from the specified view. The fields to get have to be already in the view. It produces static record(s) and costs little time. See Select (View).

SELECT <* | expression [ AS field_alias ] [, ...]>
  FROM view_name
  [ WHERE search_condition ];

INSERT

Insert data into the specified stream. It can be a data record, a JSON value or binary data. See INSERT.

INSERT INTO stream_name (field_name [, ...]) VALUES (field_value [, ...]);
INSERT INTO stream_name VALUES 'json_value';
INSERT INTO stream_name VALUES "binary_value";

DROP

Delete a given stream or view. There can be an optional IF EXISTS config to only delete the given category if it exists.

DROP STREAM    stream_name    [IF EXISTS];
DROP VIEW      view_name      [IF EXISTS];

SHOW

Show the information of all streams, queries, views or connectors.

SHOW STREAMS;
SHOW QUERIES;
SHOW VIEWS;
SHOW CONNECTORS;