[SQL] Pseudocode for SQL query

Hi guys i have the following question,

Assume tables foo(a int, b int) and bar(a int, b int) and assume you are given a stream ‘TableReader’ that reads rows from a table that has the following methods: tr.next() returns the next row of a type ‘row’ from the stream if there is a next row or null if there are no more rows. Assume columns can be accessed using row[columnName]. For example, to read rows from foo, you have to do the following: foo_stream = TableReader(‘foo’); row = foo_stream.next();

row[‘a’] will return the value of column a and row[‘b’] will return the value of column b.

Write a pseudocode to compute the results of the following SQL query which should return a list of rows: select foo.a, foo.b, bar.a, bar.b from foo, bar where foo.a = bar.a and foo.b <=100;

Can anyone help me on this ? The solution i tried is:

Foo_stream = TableReader(‘foo’);
Bar_stream = tableReader(‘bar’);


While(foo_stream.next())
{
{
While(bar_stream.next())
{
Row_foo = foo_stream.next();
Row_Bar =bar_stream.next();
{
If((row_foo[a] equals row_bar[a]) AND (row_foo < = 100))

{
Then print row_foo[a],row_foo, row_bar[a], row_bar
}
}
}
}


But the above solution is of complexity O(n2), any better solution is appreciated.

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