Interstage Big DataComplex Event Processing Server V1.1.0 Developer's Reference

1.2.13 Data Type Mapping

Complex event processing cannot be specified using SQL data type when RDB referencing is used.

The JDBC driver temporarily converts SQL data types to generic SQL types (java.sql.Types), and then to complex event processing language data types. The following table shows the complex event processing language data types corresponding to the generic SQL types.

Refer to the manual of the relevant JDBC driver for information on the generic SQL types corresponding to each SQL data type. Refer to "1.1.6 Data Type" for information on the data types for the complex event processing language.

Generic SQL types defined using java.sql.Types	Complex event processing language data type
CHAR VARCHAR LONGVARCHAR	string
BOOLEAN BIT	bool/boolean
SMALLINT	short
INTEGER	int/integer
BIGINT	long
REAL	float
DOUBLE FLOAT	double

Some generic SQL types that do not appear in the above correspondence table can be used if you convert the type.

General SQL types defined using java.sql.Types	Type conversion method	Complex event processing language data type
NUMERIC DECIMAL	Cast using bool, short, byte, int, long, float, or double. If the data size is greater than the conversion destination data type, data may be lost.	Type specified using cast
DATE TIME TIMESTAMP	Add the toString() method.	string

Other SQL types that do not appear above cannot be used with the complex event processing language.

Example

Example of mapping between Symfoware Server (referencing with native interface) data types and complex event processing language data types

Symfoware Server (referencing with native interface) SQL data types and complex event processing language data types are converted as shown below.

Refer to the manual of Symfoware Server for information on conversion between Symfoware Server SQL data types and generic SQL types.

Category	Symfoware Server SQL data type	Complex event processing language data type
Exact numeric type	SMALLINT	short
	INTEGER	int/integer
	NUMERIC	Cast using bool, short, byte, int, long, float, or double. If the data size is greater than the cast destination type, data may be lost. Therefore, select the type to be specified using cast according to the data size.
Approximate numeric type	REAL	float
	FLOAT(p) p=1 to 23	float
	FLOAT(p) p=24 to 52	double
	DOUBLE PRECISION	double
Datetime type	DATE	Add the toString() method.
	TIME
	TIMESTAMP
String type	CHARACTER	string
	VARCHAR	string
Language string types	NCHAR	string
	NCHAR VARYING	string
Other	BLOB	Not supported
	ROW_ID
	INTERVAL YEAR TO MONTH
	INTERVAL YEAR
	INTERVAL MONTH
	INTERVAL DAY TO HOUR
	INTERVAL DAY TO MINUTE
	INTERVAL DAY TO SECOND
	INTERVAL DAY
	INTERVAL HOUR TO SECOND
	INTERVAL HOUR
	INTERVAL MINUTE TO SECOND
	INTERVAL MINUTE
	INTERVAL SECOND

Example

The following example shows complex event processing for outputting "M_DATE" when the input event "E1", which has the "id" and "e_date" string types as properties, is input and the "M_DATE" date in the "MY_DB" database is earlier than "e_date".

@Name('EPL1')
select E1.id, db1.M_DATE.toString() from E1, sql:my_db ['SELECT M_DATE FROM MY_TBL'] as db1
  where db1.M_DATE.toString()>E1.e_date;

The following example shows complex event processing for outputting "PRICE" when the input event "E2", which has the "id" string type and the "value" int type as properties, is input and the value of "PRICE" in the "MY_DB" database is greater than "value".

@Name('EPL2')
select E2.id, cast(db2.PRICE, double) from E2, sql:mydb_db ['SELECT PRICE FROM MY_TBL'] as db2
  where cast(db2.PRICE, double)>E2.value;