在JSP中運行多行SQL查詢

Question

我有這樣的JSP：

ResultSet rs = st.executeQuery("select s.folderEntry,p.id,p.title,"+
    "max(case when s.name = 'event_types' then s.stringValue end) as Event_Type,"+
    "max(case when s.name = 'attendees_no' then s.stringValue end) as No_of_Attendee,"+
    "max(case when s.name = 'booker' then s.stringValue end) as Booker,"+
    "max(case when s.name = 'startdate' then s.stringValue end) as Start_date,"+
    "max(case when s.name = 'starttime' then s.stringValue end) as Start_time,"+
    "max(case when s.name = 'enddate' then s.stringValue end) as End_date,"+
    "max(case when s.name = 'endtime' then s.stringValue end) as End_time,"+
    "max(case when s.name = 'actual_attendees_no' then s.stringValue end) as Actual_Attendees_No,"+
    "max(case when s.name = 'edb' then s.stringValue end) as EDB,"+
    "max(case when s.name = 'ss_teacher' then s.stringValue end) as Secondary_School_teacher,"+
    "p.description_text"+"<br>"+
    "from sitescape.ss_folderentries"+
    "p join sitescape.ss_customattributes s on p.id = s.folderEntry"+
    "group by"+
    "p.id,"+
    "s.folderEntry");  
while(rs.next()){%>  

我收到一個錯誤：

An error occurred in a custom jsp: com.mysql.jdbc.exceptions.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'from sitescape.ss_folderentriesp join sitescape.ss_customattributes s on p.id = ' at line 1

但是我在SQL控制台中測試SQL查詢，沒有錯誤。 不知道會發生什么。 有人會暗示嗎？

Answer 1

您不在查詢中使用thml標記：

這個：

"p.description_text"+"<br>"+

應該：

p.description_text"+" "+

Answer 2

您的代碼很少有問題。 首先，在進行多行查詢時要注意空格（例如， from將被粘貼到上一行，最好在每行的末尾添加一個空格）。 其次，如果您想將<br>連接到某個字符串，請使用CONCAT(p.description_text, '<br>') （這實際上取決於您的數據庫供應商， CONCAT應該在Oracle和MySQL上運行）

ResultSet rs = st.executeQuery("select s.folderEntry,p.id,p.title, "+
  "max(case when s.name = 'event_types' then s.stringValue end) as Event_Type, "+
  "max(case when s.name = 'attendees_no' then s.stringValue end) as No_of_Attendee, "+
  "max(case when s.name = 'booker' then s.stringValue end) as Booker, "+
"max(case when s.name = 'startdate' then s.stringValue end) as Start_date, "+
"max(case when s.name = 'starttime' then s.stringValue end) as Start_time, "+
"max(case when s.name = 'enddate' then s.stringValue end) as End_date, "+
"max(case when s.name = 'endtime' then s.stringValue end) as End_time, "+
"max(case when s.name = 'actual_attendees_no' then s.stringValue end) as Actual_Attendees_No, "+
"max(case when s.name = 'edb' then s.stringValue end) as EDB, "+
"max(case when s.name = 'ss_teacher' then s.stringValue end) as Secondary_School_teacher, "+
"CONCAT(p.description_text, '<br>') "+
"from sitescape.ss_folderentries "+
"p join sitescape.ss_customattributes s on p.id = s.folderEntry "+
"group by "+
 "p.id, "+
  "s.folderEntry"); 

Answer 3

在SQL查詢中輸入HTML標記的第一件事，是<br>刪除該標記。

ResultSet rs = st.executeQuery("select s.folderEntry,p.id,p.title,"+
    "max(case when s.name = 'event_types' then s.stringValue end) as Event_Type,"+
    "max(case when s.name = 'attendees_no' then s.stringValue end) as No_of_Attendee,"+
    "max(case when s.name = 'booker' then s.stringValue end) as Booker,"+
    "max(case when s.name = 'startdate' then s.stringValue end) as Start_date,"+
    "max(case when s.name = 'starttime' then s.stringValue end) as Start_time,"+
    "max(case when s.name = 'enddate' then s.stringValue end) as End_date,"+
    "max(case when s.name = 'endtime' then s.stringValue end) as End_time,"+
    "max(case when s.name = 'actual_attendees_no' then s.stringValue end) as Actual_Attendees_No,"+
    "max(case when s.name = 'edb' then s.stringValue end) as EDB,"+
    "max(case when s.name = 'ss_teacher' then s.stringValue end) as Secondary_School_teacher,"+
    "p.description_text "+
    "from sitescape.ss_folderentries "+
    "p join sitescape.ss_customattributes s on p.id = s.folderEntry "+
    "group by "+
    "p.id,"+
    "s.folderEntry");  
while(rs.next()){%> 

Answer 4

您的SQL僅在Java代碼中是多行的。 但是您正在使用字符串連接。 因此，它僅將""標記內的內容加在一起。

這意味着不同部分之間沒有空格，並且<br>不是有效的SQL。

例如，這部分：

"p.description_text"+"<br>"+
"from sitescape.ss_folderentries"+
"p join sitescape.ss_customattributes s on p.id = s.folderEntry"+
"group by"+
"p.id,"+

會給你這個字符串：

p.description_text<br>from sitescape.ss_folderentriesp join sitescape.ss_customattributes s on p.id = s.folderEntrygroup byp.id,

如您所見，別名p已添加到sitescape.ss_folderentries ，成為sitescape.ss_folderentriesp ，就SQL而言，它不是它知道的表的名稱。 s.folderEntrygroup和byp.id相同，您確實希望s.folderEntry group by p.id成為s.folderEntry group by p.id

因此，基本上，您應該在每個串聯部分的開頭添加一個空格。 這將解決單詞粘在一起的問題。

您對<br>的意圖是<br> ？ 您是要在說明文字中添加<br>嗎？ 如果是這樣，它應該用單引號引起來。

" p.description_text + '<br>'"

（假設您的SQL文本串聯運算符為+ ）