我在自动化组件测试中使用 HSQLDB 作为数据库。它模拟生产的 Oracle 数据库。
在我的 SQL 代码中，我在模式范围内定义了一个序列，例如
CREATE SEQUENCE THE_SCHEMA.THE_SEQUENCE ... ;
然后当我从这个模式中获取 nextval 时：
Connection con = ...
String query = "SELECT THE_SCHEMA.THE_SEQUENCE.nextval as MyNextVal from DUAL;"
PreparedStatement ps = con.prepareStatement(query);
ResultSet resultSet = ps.executeQuery();
我在 con.prepareStatement(query) 调用中收到如下错误。
当我在全局范围内定义序列时，上面的代码运行良好，如下所示
CREATE SEQUENCE THE_SEQUENCE ... ;
和改变
String query = "SELECT THE_SEQUENCE.nextval as MyNextVal from DUAL;"
我的问题是 HSQL 是否支持模式级别序列？
我错过了什么吗？
（我使用 SET DATABASE SQL SYNTAX ORA TRUE 打开了“Oracle 兼容模式”；）
堆栈跟踪：
Caused by: java.lang.NullPointerException
at org.hsqldb.RangeVariable.resolvesSchemaName(Unknown Source)
at org.hsqldb.RangeVariable.resolvesSchemaAndTableName(Unknown Source)
at org.hsqldb.RangeVariable.findColumn(Unknown Source)
at org.hsqldb.ExpressionColumn.resolveColumnReference(Unknown Source)
at org.hsqldb.ExpressionColumn.resolveColumnReferences(Unknown Source)
at org.hsqldb.QuerySpecification.resolveColumnReferencesAndAllocate(Unknown Source)
at org.hsqldb.QuerySpecification.resolveColumnReferences(Unknown Source)
at org.hsqldb.QuerySpecification.resolveReferences(Unknown Source)
at org.hsqldb.QueryExpression.resolve(Unknown Source)
at org.hsqldb.ParserDQL.compileCursorSpecification(Unknown Source)
at org.hsqldb.ParserCommand.compilePart(Unknown Source)
at org.hsqldb.ParserCommand.compileStatement(Unknown Source)
at org.hsqldb.Session.compileStatement(Unknown Source)
at org.hsqldb.StatementManager.compile(Unknown Source)
... 26 more
java.sql.SQLException: java.lang.NullPointerException java.lang.NullPointerException
at org.hsqldb.jdbc.JDBCUtil.sqlException(Unknown Source)
at org.hsqldb.jdbc.JDBCUtil.sqlException(Unknown Source)
at org.hsqldb.jdbc.JDBCPreparedStatement.<init>(Unknown Source)
at org.hsqldb.jdbc.JDBCConnection.prepareStatement(Unknown Source)
从 con.prepareStatement(query) 抛出的异常的详细信息：
Exception type java.sql.SQLException
cause = org.hsqldb.HsqlException: java.lang.NullPointerException
detailMessage = java.lang.NullPointerException java.lang.NullPointerException
next = null
SQLState = S1000
stackTrace = null
vendorCode = -458