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#pragma once
#include "QueryStr.h"
namespace sql {
class DBConnection;
class Statement;
/**
* A query that can be cached by a connection.
*
* Mainly intended for use with the language extension. The idea is that the language extension
* generates a CachedQuery instance and passes it to `DBConnection.prepare`. This causes
* connection to prepare the query and then cache it for the duration of the connection itself.
*
* This scheme is also designed to allow supplying different versions of the query based on the
* capabilities of the underlying database (e.g. work-arounds for databases that don't support
* the RETURNS clause of insert statements for example).
*/
class CachedQuery : public Object {
STORM_ABSTRACT_CLASS;
public:
// Create.
STORM_CTOR CachedQuery() {}
// Prepare a query for a particular database to produce a statement. The expectation is that
// the implementation calls `db.prepare(<query>)` and returns the result. However, this
// scheme also allows returning some more complex statement, e.g. for compatibility.
virtual Statement *STORM_FN query(DBConnection *db) ABSTRACT;
};
}
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