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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.

sql
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.

sql
CREATE VIEW view_name AS select_query;

SELECT ​

Get records from a materialized view or a stream. Note that SELECT from streams can only used as a part of CREATE STREAM or CREATE VIEW. When you want to get results in a command-line session, create a materialized view first and then SELECT from it. See SELECT (Stream).

sql
SELECT <* | expression [ AS field_alias ] [, ...]>
  FROM stream_ref
  [ WHERE expression ]
  [ GROUP BY field_name [, ...] ]
  [ HAVING expression ];

INSERT ​

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

sql
INSERT INTO stream_name (field_name [, ...]) VALUES (field_value [, ...]);
INSERT INTO stream_name VALUES CAST ('json_value'   AS JSONB);
INSERT INTO stream_name VALUES CAST ('binary_value' AS BYTEA);
INSERT INTO stream_name VALUES 'json_value'   :: JSONB;
INSERT INTO stream_name VALUES 'binary_value' :: BYTEA;

DROP ​

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

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

SHOW ​

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

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