Incorrect, table 1 (source of new data) has 4000 rows (has 2 columns - 1st column has 4000 data, same data as 1st column of table 2) and table 2 has 6000 rows (has more data and many rows are inserted by users, is more accurate of table 1, but with empty cells in column 2, cells to be updated with the content from source table, from column 2).I have to insert new data into table 2 (table with 6000 rows) into 2nd column, but only where data in 1st column of table 1 and table 2 are the same. Order of data in two tables (1st column) is not the same. Many data in table 2 are in last months deleted