執行多行查詢不適用於單行查詢所在的表別名

Question

這是我第一次使用ucanaccess，因爲我剛發現我的以前版本的Eclipse不能用於Java 1.8，所以我可以訪問我的Access DB 。我熟悉Java編程和RDBMS（目前使用Oracle），所以我不明白爲什麼我的代碼出現錯誤。

這是我使用連接到DB中的碼（可變DBFILE是用來存儲訪問DB路徑的文件對象）：

\t \t try 
 
\t \t { 
 
\t \t \t String urlDB = "jdbc:ucanaccess://"+ dbFile.getAbsolutePath(); 
 
\t \t \t 
 
\t \t \t Connection conn = DriverManager.getConnection(urlDB, "", ""); 
 
\t \t \t System.out.println("Connection Successful\n"); 
 
\t \t \t 
 
\t \t \t Statement test = conn.createStatement(); 
 
/* \t \t \t ResultSet rs = test.executeQuery("SELECT e.* " 
 
                 + "FROM Employees e" 
 
                 + "WHERE e.EmployeeNo LIKE 'H%'" 
 
                 + "ORDER BY e.LastName"); 
 

 
\t \t \t System.out.println(); //spacing 
 

 
\t \t \t //retrieve column data 
 
\t \t \t while(rs.next()) 
 
\t \t \t { 
 
\t \t \t \t //can get data by column name instead of ID 
 
\t \t \t \t String id = rs.getString("ID"); 
 
\t \t \t \t String fName = rs.getString("FirstName"); 
 
\t \t \t \t String lName = rs.getString("LastName"); 
 
\t \t \t \t String dName = rs.getString("DisplayName"); 
 
\t \t \t \t \t \t 
 
\t \t \t \t System.out.println(id + "\t" + fName + "\t" + lName + "\t"); 
 
\t \t \t \t 
 
\t \t \t } 
 
*/ \t \t \t 
 
\t \t \t ResultSet rs = test.executeQuery("SELECT e.* FROM Employees e WHERE e.EmployeeNo LIKE '1%' ORDER BY e.LastName"); 
 
\t \t \t 
 
\t \t \t //get table information (i.e. column names) 
 
\t \t \t ResultSetMetaData rsmd = rs.getMetaData(); 
 
\t \t \t int dbColumnCount = rsmd.getColumnCount(); 
 
\t \t \t 
 
/* \t \t \t //db columns starts at 1 not 0 
 
\t \t \t for (int count = 1; count <= dbColumnCount; count++) 
 
\t \t \t { 
 
\t \t \t \t System.out.print(rsmd.getColumnName(count) + "\t"); 
 
\t \t \t } 
 
*/ \t \t \t 
 
\t \t \t System.out.format("%5s%10s%15s%20s%n", rsmd.getColumnName(1), rsmd.getColumnName(2), 
 
\t \t \t \t \t rsmd.getColumnName(3), rsmd.getColumnName(4)); 
 
\t \t \t //System.out.println(); 
 
\t \t \t 
 
\t \t \t while(rs.next()) 
 
\t \t \t { 
 
\t \t \t \t //can get data by column name instead of ID 
 
\t \t \t \t String id = rs.getString("ID"); 
 
\t \t \t \t String fName = rs.getString("FirstName"); 
 
\t \t \t \t String lName = rs.getString("LastName"); 
 
\t \t \t \t String dName = rs.getString("DisplayName"); 
 
\t \t \t \t \t \t 
 
\t \t \t \t //System.out.println(id + "\t" + fName + "\t" + lName + "\t"); 
 
\t \t \t \t System.out.format("%5s%10s%15s%20s%n", id, fName, lName, dName); 
 
\t \t \t } 
 
\t \t \t 
 
\t \t } 
 
\t \t catch (Exception e) 
 
\t \t { 
 
\t \t \t e.printStackTrace(); 
 
\t \t \t System.err.println("Could not connect to the Database"); 
 
\t \t \t System.err.println(e.getMessage()); 
 
\t \t } \t \t 
 
\t }

到結果集的第一個呼叫（多行查詢）拋出了以下異常：

net.ucanaccess.jdbc.UcanaccessSQLException: UCAExc:::4.0.0 user lacks privilege or object not found: E 
 
\t at net.ucanaccess.jdbc.UcanaccessStatement.executeQuery(UcanaccessStatement.java:210) 
 
\t at DBConnect.<init>(InOutBoard.java:78) 
 
\t at InOutBoard.main(InOutBoard.java:47) 
 
Caused by: java.sql.SQLSyntaxErrorException: user lacks privilege or object not found: E 
 
\t at org.hsqldb.jdbc.JDBCUtil.sqlException(Unknown Source) 
 
\t at org.hsqldb.jdbc.JDBCUtil.sqlException(Unknown Source) 
 
\t at org.hsqldb.jdbc.JDBCStatement.fetchResult(Unknown Source) 
 
\t at org.hsqldb.jdbc.JDBCStatement.executeQuery(Unknown Source) 
 
\t at net.ucanaccess.jdbc.UcanaccessStatement.executeQuery(UcanaccessStatement.java:208) 
 
\t ... 2 more 
 
Caused by: org.hsqldb.HsqlException: user lacks privilege or object not found: E 
 
\t at org.hsqldb.error.Error.error(Unknown Source) 
 
\t at org.hsqldb.error.Error.error(Unknown Source) 
 
\t at org.hsqldb.QuerySpecification.resolveColumnReferencesForAsterisk(Unknown Source) 
 
\t at org.hsqldb.QuerySpecification.resolveReferences(Unknown Source) 
 
\t at org.hsqldb.QueryExpression.resolve(Unknown Source) 
 
\t at org.hsqldb.ParserDQL.compileCursorSpecification(Unknown Source) 
 
\t at org.hsqldb.ParserCommand.compilePart(Unknown Source) 
 
\t at org.hsqldb.ParserCommand.compileStatements(Unknown Source) 
 
\t at org.hsqldb.Session.executeDirectStatement(Unknown Source) 
 
\t at org.hsqldb.Session.execute(Unknown Source) 
 
\t ... 5 more 
 
Could not connect to the Database 
 
UCAExc:::4.0.0 user lacks privilege or object not found: E

而如果我運行第二次調用ResultSet（單行查詢），數據從表中正確返回。現在據我所知（除了在第一行中跨越多行），兩個查詢都是相同的。那爲什麼第一個拋出錯誤呢？我無法想象格式的選擇會有所作爲，但正如我所說，我知道使用ucanaccess。

任何幫助，將不勝感激。提前致謝！

Answer 1

的聯繫，我經常給有效這裏太：
How to debug dynamic SQL in VBA

您串聯SQL字符串，不檢查是正確的。

ResultSet rs = test.executeQuery("SELECT e.* " 
           + "FROM Employees e" 
           + "WHERE e.EmployeeNo LIKE 'H%'" 
           + "ORDER BY e.LastName"); 

將導致

SELECT e.* FROM Employees eWHERE e.EmployeeNo LIKE 'H%'ORDER BY e.LastName 

它遺漏換行之間的空格。