Diesel assumes that your table name is the plural, snake-case form of your struct name. Because your table name does not follow this convention you can specify the table name explicitly:
#[derive(Queryable, Identifiable)]#[table_name = "category"]pub struct Category { // ...}#[derive(Queryable, Identifiable)]#[table_name = "correspondent"]pub struct Correspondent { // ...}// and do the same to the rest of your models...