casting - cast access text to numeric -

i'm working in access 2007. have couples of tables i've imported excel in link mode, access makes copy of them , can use them in read mode. i'm in trouble cast. primary key text in first table , integer in other one. want make first 1 numeric field.

i assume left table "lansweeper_jacopobelloni" , right table "pc_carelhq_modificato". have 3 queries, 1 inner join because there must (1,1) relation beetween 2 tables. right join check there in left table there in right one. have left join find in right table in left one.

how can cast string integer in order apply comparison?

like operator not best use, specially wit text field. suggest 2 alternatives.

first : create new column in table number type , update numeric value of text field, change pk new field , delete old field. (most ideal).

second : create query join 2 tables. better alternative operator. like;

select table1.id, table2.someotherfield table1 inner join table2  on clng(table1.id) = table2.id_fk;