Why Does Retrieving Data from a ResultSet Throw a 'Before Start of Result Set' Exception?

ResultSet Exception: "Before Start of Result Set"

When retrieving data from a ResultSet object, it's crucial to position the cursor correctly to avoid exceptions. In the provided code snippet:

ResultSet result = prep.executeQuery();
result.beforeFirst();

The cursor is initially positioned before the first row in the result set using result.beforeFirst(). Subsequently, an attempt is made to retrieve data from the "first" row using result.getString(1):

String foundType = result.getString(1);

However, since the cursor is not currently pointing to any row, this operation triggers the "Before start of result set" exception.

The correct approach is to move the cursor to the first row before retrieving data:

result.next();
String foundType = result.getString(1);

This ensures that the cursor points to the actual first row in the result set, allowing you to access data successfully.

In summary, when working with ResultSet objects, it's essential to position the cursor correctly either by performing result.next() or using conditional checks and loops to iterate through the results. This avoids exceptions and ensures that data retrieval operations are performed on the appropriate rows.

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