Language Reference Guide : System Classes : DataStream Class : QueryMode Attribute
 
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QueryMode Attribute
Data Type: smallint
4GL Access: R
The QueryMode attribute specifies the current mode of the query.
Valid values are:
QY_CACHE
Specifies that the retrieved data set is cached in a file, allowing previous navigation and random seek. It requires the Load and NextRow methods to display data.
QY_CURSOR
Specifies that the retrieved data set uses a DBMS cursor, allowing nested queries. It requires the Load and NextRow methods to display data.
QY_DIRECT
Specifies that the retrieved data set is returned as in a select loop. It precludes nested queries because a single select statement is in effect between the Open and Close of the DataStream object. It also requires the Load and NextRow methods to display data.
QY_ARRAY
Specifies that the retrieved data set is immediately loaded into the specified table field or local array by the Open method (making the Load and NextRow methods meaningless). It requires the UpdField method to refresh the display.
Using QY_ARRAY mode enhances performance if you are loading a table field because an entire array of data is loaded. However, to take advantage of the enhanced performance, the class of the array being loaded must have attribute names that match the names of the columns in the query (which can differ from the names of columns in underlying database tables, due to "as" clauses).
Descriptions of system constant values and their numeric equivalents are listed in Query Modes.