org.d2rq.r2rml
Class SQLQuery
java.lang.Object
org.d2rq.r2rml.MappingTerm
org.d2rq.r2rml.SQLQuery
public class SQLQuery
- extends MappingTerm
A SQL query is a SELECT query in the SQL language that can be executed
over the input database. The string must conform to the production
"direct select statement: multiple rows" in [SQL2] with an optional
trailing semicolon character and optional surrounding white space
(excluding comments) as defined in [TURTLE]. It must be valid to
execute over the SQL connection. The result of the query execution
must not have duplicate column names. Any columns in the SELECT list
derived by projecting an expression should be named, because otherwise
they cannot be reliably referenced in the rest of the mapping.
Database objects referenced in the SQL query may be qualified with a
catalog or schema name. For any database objects referenced without an
explicit catalog name or schema name, the default catalog and default
schema of the SQL connection are assumed.
- See Also:
- R2RML: SQL query
create
public static SQLQuery create(String sql)
- Always succeeds. Check
MappingTerm.isValid()
to see if syntax is ok.
- Returns:
null
if arg is null
toString
public String toString()
- Overrides:
toString
in class Object
accept
public void accept(MappingVisitor visitor)
- Specified by:
accept
in class MappingTerm
equals
public boolean equals(Object other)
- Overrides:
equals
in class Object
hashCode
public int hashCode()
- Overrides:
hashCode
in class Object