Why Am I Getting a 'Before Start of Result Set' Exception in JDBC?

JDBC ResultSet Issue: "Before Start of Result Set" Exception

When attempting to retrieve data from a ResultSet object, an error may occur stating "Before start of result set." This error typically arises due to a positioning issue with the cursor within the ResultSet.

In the provided code snippet, the ResultSet is positioned before the first row using result.beforeFirst(). Subsequently, an attempt is made to retrieve data using result.getString(1) without first moving the cursor to a valid row.

To resolve this issue, the cursor should be positioned to the first row before attempting to retrieve data. This can be achieved by either using result.next() or result.first() methods.

Corrected Code:

ResultSet result = prep.executeQuery();
result.next(); // Move the cursor to the first row
String foundType = result.getString(1);

Alternatively, if it's unsure whether the ResultSet contains any data, an if statement can be used to check for data before attempting to move the cursor:

if (result.next()) {
    String foundType = result.getString(1);
}

By ensuring that the cursor is positioned to a valid row before retrieving data, the "Before start of result set" exception can be avoided, and data can be obtained successfully from the ResultSet.

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