Question

I have a doubt about adding days to Date in MySQL database.
The following is my code:

res=stat.executeQuery("select st_date from tmp1 where st_date = '"+t1.getText()+"'");
while(res.next())
{
    System.out.println(res.getDate(1));
    int i=0;
    while(i<14)
    {
        statement.executeUpdate("Insert into datetab values(DATE_ADD('"
            +res.getDate("st_date")+"',INTERVAL 1 DAY),'"+tempname+"')");
        i=i+1;
    }
}

All the updates in datetab table occur, but there is a problem. I will explain the problem with an example. If the date from tmp1 table is 28-12-2000, then after executing the insert query with date_add(), what happens is that 13 new inserts are happening, but all those inserts are “29-12-2000”.

Answer 1

If the date from tmp1 table is 28-12-2000 Then after executing the insert query with date_add(), what happens is that 13 new inserts are happening, but all those inserts are “29-12-2000”.

Because that is exactly what you are asking for. Your insert statement is:

"Insert into datetab values(DATE_ADD('" + res.getDate("st_date") + 
    "',INTERVAL 1 DAY),'" + tempname + "')"

Since read.getDate is not changing in the loop, the same value is inserted in every interation.

Instead of "Interval 1 DAY", use "Interval " + i + " Day" should insert different days. Is that what you are looking for?