select語句出現錯誤，union all都在子查詢中

Question

在Oracle 11g中，我遇到了查詢錯誤，無法確定它爲什麼會出錯。以下是查詢：

select 
    main_data.issue_number, 
    main_data.transaction_number 
from 
(
    select 
     p1.payment_date, 
     p1.media_number, 
     p1.payment_amount, 
     p1.issue_number, 
     p1.advice_na_number, 
     name.name_address_line_1, 
     name.name_address_line_2, 
     name.name_address_line_3, 
     name.name_address_line_4, 
     name.name_address_line_5, 
     name.name_address_line_6, 
     name.name_address_line_7, 
     name.name_address_city, 
     name.state_code, 
     name.address_country_code, 
     name.zip_code, 
     name.tax_id_number, 
     p1.output_tx_number_prin, 
     p1.output_tx_number_int, 
     '' as "transaction_number", 
     p1header.check_account_number 

    from 
    p1 
    left join name on p1.name_address_number = name.name_address_number 
    left join p1header on p1.issue_number = p1header.issue_number 

    UNION ALL 

    select 
     check.date_of_payment, 
     check.media_number, 
     check.payment_amount, 
     check.issue_number, 
     check.payee_na_number, 
     name.name_address_line_1, 
     name.name_address_line_2, 
     name.name_address_line_3, 
     name.name_address_line_4, 
     name.name_address_line_5, 
     name.name_address_line_6, 
     name.name_address_line_7, 
     name.name_address_city, 
     name.state_code, 
     name.address_country_code, 
     name.zip_code, 
     name.tax_id_number, 
     '' as "output_tx_number_prin", 
     '' as "output_tx_number_int", 
     check.transaction_number, 
     check.dda_number as "check_account_number" 
    from check 
    left join name on check.payee_na_number = name.name_address_number 
) main_data 

選擇上面的單個字段會給我一個「無效的標識符錯誤」。如果我這樣做select *那麼它會給我回數據沒有任何錯誤。我在這裏做錯了什麼？謝謝。

Answer 1

舊引用標識符問題...請參閱database object naming documentation中的第9點，並注意Oracle不建議使用帶引號的標識符。

您已將列別名作爲小寫字母放在雙引號內。這意味着任何對它的引用也必須被引用並且與案例完全匹配。因此，這會工作：

select 
    main_data.issue_number, 
    main_data."transaction_number" 
from 
... 

但是，除非你有一個燃燒需要有一個別名，這樣的 - 我懷疑你從實際的表列中的所有標識符名稱中沒有報價 - 這將是簡單從內選擇刪除雙引號：

select 
    main_data.issue_number, 
    main_data.transaction_number 
from 
(
    select 
    ... 
     '' as transaction_number, 
     p1header.check_account_number 
    ... 
    UNION ALL 
    select 
    ... 
     '' as output_tx_number_prin, 
     '' as output_tx_number_int, 
     check.transaction_number, 
     check.dda_number as check_account_number 
    ... 

你實際上並不需要向別名工會的第二分支中的列;列標識符將全部來自第一分支。