I'm a MySQL user and I have been using following statements in MySQL Workbench : (these statements are based on Select column names whose entries are not null )
SET group_concat_max_len = 4294967295;
SELECT GROUP_CONCAT(
' SELECT ',QUOTE(COLUMN_NAME),
' FROM ( select * from table_name where s3_01 = ', coloumn1,' ) abc',
' WHERE `',REPLACE(COLUMN_NAME, '`', '``'),'` IS NOT NULL',
' HAVING COUNT(*)'
SEPARATOR ' UNION ALL ')
INTO @sql
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_SCHEMA = DATABASE()
AND TABLE_NAME = 'table_name';
PREPARE stmt FROM @sql;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;
Although it work in my workbench, I do not know how to make it work in java. for example, I made following code:
String sql1 = "SET group_concat_max_len = 4294967295;";
String sql2 = " SELECT GROUP_CONCAT(' SELECT ',QUOTE(COLUMN_NAME), ' FROM ( select * from ptc_weight where s3_01 = ',column1,' ) abc', ' WHERE `',REPLACE(COLUMN_NAME, '`', '``'),'` IS NOT NULL', ' HAVING COUNT(*)' SEPARATOR ' UNION ALL ') INTO @sql FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = 'ptc_weight'; ";
String sql3 = " PREPARE stmt FROM @sql; ";
String sql4 = " EXECUTE stmt;";
String sql5 = " DEALLOCATE PREPARE stmt;";
String[] result = getResult(sql1+sql2+sql3+sql4+sql5);
public static String[][] getResult(String sql) {
System.out.println(sql);
Connection con = null;
PreparedStatement ps = null;
ResultSet rs = null;
String[][] resultTable = null;
try {
con = getCon();
ps = con.prepareStatement(sql);
rs = ps.executeQuery();
ResultSetMetaData result = rs.getMetaData();
int rowNum=0;
// Go to the last row
rs.last();
rowNum = rs.getRow();
// Reset row before iterating to get data
rs.beforeFirst();
int colNum = result.getColumnCount();
resultTable = new String[rowNum][colNum];
for(int itr1=0; itr1<rowNum; itr1++){
rs.next();
for(int itr2=0; itr2<colNum; itr2++){
resultTable[itr1][itr2] = rs.getObject(itr2+1).toString();
}
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally {
dbclose(con, ps, rs);
}// finally
return resultTable;
}
However, it does not work. I guess I made a wrong code for utilizing stored procedure, but I don't have any idea to deal with this problem.
CallableStatement callableStatement = null;
String getDBUSERByUserIdSql = "{call getDBUSERByUserId(?,?,?,?)}";
callableStatement.setInt(1, 10);
callableStatement.registerOutParameter(2, java.sql.Types.VARCHAR);
callableStatement.registerOutParameter(3, java.sql.Types.VARCHAR);
callableStatement.registerOutParameter(4, java.sql.Types.DATE);
// execute getDBUSERByUserId store procedure
callableStatement.executeUpdate();
String userName = callableStatement.getString(2);
String createdBy = callableStatement.getString(3);
Date createdDate = callableStatement.getDate(4);
System.out.println("UserName : " + userName);
System.out.println("CreatedBy : " + createdBy);
System.out.println("CreatedDate : " + createdDate);
Here Is Full Example . You can modify your code as you need.
Simple one with less argument and with resultset :
CallableStatement cstmt = con.prepareCall("{call getEmployeeDetails(?, ?)}");
cstmt.setInt("employeeId", 123);
cstmt.setInt("companyId", 456);
ResultSet rs = cstmt.executeQuery();
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