The FETCH statement can be modified to fetch more than one row at a time, which may improve performance. This is called a wide fetch or an array fetch.
To use wide fetches in embedded SQL, include the fetch statement in your code as follows:
EXEC SQL FETCH ... ARRAY nnn
where ARRAY nnn is the last item of the FETCH statement. The fetch count nnn can be a host variable. The number of variables in the SQLDA must be the product of nnn and the number of columns per row. The first row is placed in SQLDA variables 0 to (columns per row) - 1, and so on.
Each column must be of the same type in each row of the SQLDA, or a SQLDA_INCONSISTENT error is returned.
The server returns in SQLCOUNT the number of records that were fetched, which is always greater than zero unless there is an error or warning. On a wide fetch, a SQLCOUNT of one with no error condition indicates that one valid row has been fetched.
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