ResultSet

title: ResultSet in JDBC description: ResultSet se data retrieve karna

SQL query ke results hold karta hai. Cursor concept use karta hai.

Basic Navigation

java exampleWoHoTech

ResultSet rs = stmt.executeQuery("SELECT * FROM students");

// Default: Forward only, read-only
while (rs.next()) {
    // By index (1-based)
    int id = rs.getInt(1);
    String name = rs.getString(2);
    
    // By column name (preferred)
    int id2 = rs.getInt("id");
    String name2 = rs.getString("name");
    double marks = rs.getDouble("marks");
    
    // Null check
    if (rs.wasNull()) System.out.println("Value was null");
}

ResultSet Types

java exampleWoHoTech

// TYPE_FORWARD_ONLY (default)
Statement s1 = conn.createStatement();

// TYPE_SCROLL_INSENSITIVE — scroll, DB changes nahi dikhe
Statement s2 = conn.createStatement(
    ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_READ_ONLY);

// TYPE_SCROLL_SENSITIVE — scroll, DB changes dikhe
Statement s3 = conn.createStatement(
    ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_UPDATABLE);

Scrollable ResultSet Methods

java exampleWoHoTech

rs.first()          // First row
rs.last()           // Last row
rs.next()           // Next row
rs.previous()       // Previous row
rs.absolute(3)      // Row number 3
rs.relative(-2)     // Current - 2
rs.isFirst()        // First row hai?
rs.isLast()         // Last row hai?
rs.getRow()         // Current row number

ResultSetMetaData

ResultSetMetaData meta = rs.getMetaData(); int cols = meta.getColumnCount(); for (int i = 1; i <= cols; i++) { System.out.println(meta.getColumnName(i) + " - " + meta.getColumnTypeName(i)); }

title: ResultSet in JDBC description: ResultSet se data retrieve karna

SQL query ke results hold karta hai. Cursor concept use karta hai.

Basic Navigation

java exampleWoHoTech

ResultSet rs = stmt.executeQuery("SELECT * FROM students");

// Default: Forward only, read-only
while (rs.next()) {
    // By index (1-based)
    int id = rs.getInt(1);
    String name = rs.getString(2);
    
    // By column name (preferred)
    int id2 = rs.getInt("id");
    String name2 = rs.getString("name");
    double marks = rs.getDouble("marks");
    
    // Null check
    if (rs.wasNull()) System.out.println("Value was null");
}

ResultSet Types

java exampleWoHoTech

// TYPE_FORWARD_ONLY (default)
Statement s1 = conn.createStatement();

// TYPE_SCROLL_INSENSITIVE — scroll, DB changes nahi dikhe
Statement s2 = conn.createStatement(
    ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_READ_ONLY);

// TYPE_SCROLL_SENSITIVE — scroll, DB changes dikhe
Statement s3 = conn.createStatement(
    ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_UPDATABLE);

Scrollable ResultSet Methods

java exampleWoHoTech

rs.first()          // First row
rs.last()           // Last row
rs.next()           // Next row
rs.previous()       // Previous row
rs.absolute(3)      // Row number 3
rs.relative(-2)     // Current - 2
rs.isFirst()        // First row hai?
rs.isLast()         // Last row hai?
rs.getRow()         // Current row number

ResultSetMetaData

ResultSetMetaData meta = rs.getMetaData(); int cols = meta.getColumnCount(); for (int i = 1; i <= cols; i++) { System.out.println(meta.getColumnName(i) + " - " + meta.getColumnTypeName(i)); }

ResultSet

Basic Navigation

ResultSet Types

Scrollable ResultSet Methods

ResultSetMetaData

Continue learning this concept

ResultSet

Basic Navigation

ResultSet Types

Scrollable ResultSet Methods

ResultSetMetaData

Continue learning this concept