Java wrapper.select(DISTINCT) - Eliminate Duplicate Rows in SQL Queries
The code you provided is not complete, as it only includes the method call "wrapper.select(DISTINCT)". \n\nIn Java, the "select()" method is typically used in database queries to retrieve data from a table. However, the "DISTINCT" keyword is used in the SQL query to eliminate duplicate rows from the result set. \n\nHere's an example of how you can use "select()" method with "DISTINCT" keyword in a Java program:\n\njava\nimport java.sql.Connection;\nimport java.sql.DriverManager;\nimport java.sql.ResultSet;\nimport java.sql.SQLException;\nimport java.sql.Statement;\n\npublic class Main {\n public static void main(String[] args) {\n String url = \"jdbc:mysql://localhost:3306/mydatabase\";\n String username = \"root\";\n String password = \"password\";\n\n try (Connection connection = DriverManager.getConnection(url, username, password);\n Statement statement = connection.createStatement()) {\n \n String query = \"SELECT DISTINCT column_name FROM table_name\";\n ResultSet resultSet = statement.executeQuery(query);\n\n while (resultSet.next()) {\n String value = resultSet.getString(\"column_name\");\n System.out.println(value);\n }\n } catch (SQLException e) {\n e.printStackTrace();\n }\n }\n}\n\n\nIn this example, we establish a connection to a MySQL database using JDBC. Then, we create a statement object to execute the SQL query. The query includes the "SELECT DISTINCT" clause to retrieve only distinct values from the specified column. The result set is then iterated to print the retrieved values.
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