开发者

Is there a way to reference field name with a variable in Firebird

开发者 https://www.devze.com 2023-04-12 04:05 出处:网络
Is there a way to开发者_C百科 reference field name with a variable value in Firebird ? for example I want to make SQL like this:

Is there a way to开发者_C百科 reference field name with a variable value in Firebird ? for example I want to make SQL like this:

Insert into tab1 (1, f1, f2, f3)
    select 1, tab2.f+var_loop, tab2.f+var_loop, tab2.f+var_loop
    from tab2
    where .....

where "f" is the first initial of the field name and "var_loop" is a loop variable Thanks


No, this is not supported. I quess you can achieve something like this using EXECUTE BLOCK, but then you could build the right SQL statement on the client side right away too, would be much easier...


To do this, you must write your application code to build the SQL prior to preparing the query.

In SQL, the name and number of columns must be fixed at the time you prepare the query. Column names can't be based on expressions that aren't evaluated until runtime. This is true in standard SQL and in every brand of RDBMS as far as I know.

Also you can't use parentheses around a list of column in a SELECT clause as you're doing.

0

精彩评论

暂无评论...
验证码 换一张
取 消

关注公众号