IRIS for UNIX 2019.2
The %DynamicSQLQuery class is used for defining class queries based on runtime SQL statements.
Close the query associated with the handle
Execute is passed parameters for Query. Returns handle for subsequent operations.
Fetch the next row of data from the query.
qHandle is query-defined data and is typically updated by Fetch.
The Fetch method should set Row to be a $List of values corresponding to the columns of the query. If we are past the end of the data and no row is returned, Row should be set to null string (""). If the non-empty row being returned is the last one, AtEnd could be optionally set to 1, indicating that an additional call to Fetch may be avoided.
Row may also be subscripted. If any of the columns in the row are stream orefs then the oref type information is lost in the Row $list encoded value. To retain the oref type, place the oref into Row(columnNumber). %Library.ResultSet recognizes this form and will extract the column value as the subscripted value.
FetchRows returns the next FetchCount rows in the query and updates handle for subsequent operations. FetchCount is the number of rows to fetch. If FetchCount is zero then up to 24k of row data is returned. ReturnCount contains the number of rows returned and AtEnd is true if there are no more rows to be fetched. This method does not preserve swizzled streams.
Returns information about the query. It is used by the various ResultSet objects.
Returns information about columns in the query result, parameters in the query formal list, and whether or not the result contains enough information to form an ID value.
This information is return in three pass-by-reference parmeters:
- colinfo - contains one list element for each column declared in ROWSPEC. The form is name:exttype:caption
- parminfo - contains one list element for each formal paramter of the query in the form name:exttype
- idinfo - contains a list, the first element indicating the position of the ID, zero if not included and the second element is the extent of these ID value.
- qHandle -
query handle, used for dynamic queries
Prepare the query for execution. For static queries, this method probably just returns $$$OK. For dynamic queries this method will set up the information returned by GetInfo. It is used by the various ResultSet objects.