Question

I am trying to use a SQL Select statement for a query in Java. I currently have the following:

ResultSet rs = stmt.executeQuery("SELECT *" +
                                             " FROM " + table + 
                                             " WHERE " + selection + 
                                             " VALUES " + selectionArgs);

where “selection” is a string and “selectionArgs” is a string array.

 String selection = "documentFK=?";
 String[] selectionArgs = { ... };

Is it possible to use the VALUES command to replace the ? like in with the INSERT command? Either way, what would be the correct syntax?

Thanks for the help.

Answer 1

no, that is not the way it’s done. first you create the statement from the query, using the question marks as place holders for the real values you want to put there. then you bind these values to the statement.

//the query
String sql = "SELECT " + "*" +
                " FROM " + table + 
                " WHERE documetFK = ?";

//create the statement
PreparedStatement stmt = connection.prepareStatement(sql);

//bind the value
stmt.setInt(1, 4); //1 is "the first question mark", 4 is some fk

//execute the query and get the result set back
ResultSet rs = stmt.executeQuery();

now, if you want this thing with selection string and some args, then you’re going to have a loop in your java code. not sure what your array looks like (you’re not giving me that much to go on), but if it’s made up from strings, it would be something like this:

//the query
String sql = "SELECT " + "*" +
                " FROM " + table + 
                " WHERE " + selection;

//create the statement
PreparedStatement stmt = connection.prepareStatement(sql);

//bind the values
for(int i = 0; i < selectionArgs.length; i++) {
    stmt.setString(i, selectionArgs[i]); //i is "the nth question mark"
}

//execute the query and get the result set back
ResultSet rs = stmt.executeQuery();