我有一个包含多个语句的小型SQL脚本：
private static final String SQL = "SELECT 1; INSERT INTO test (test) VALUES (23);";
我想使用纯JDBC针对Microsoft SQL Server执行它。由于表“ test”不存在，因此我希望引发异常。听起来很简单，但事实并非如此。如果我执行
try (Statement stmt = con.createStatement();) {
hasMoreResultSets = stmt.execute(SQL);
我没有例外。为什么？由于第一个SELECT不会触发异常，因此如果我通过调用getMoreResults（）来请求第二条语句的ResultSet，则该异常仅是thron。
while (hasMoreResultSets) {
System.out.println("Resultset found");
ResultSet rs = stmt.getResultSet();
rs.next();
rs.close();
hasMoreResultSets = stmt.getMoreResults();
}
太好了！这很麻烦但是有效。但是现在我必须使用PreparedStatement（这是一个使用PreparedStatement的开放源代码项目中的库，因此我无法通过切换到纯语句来轻松解决此问题。）切换到PreparedStatement很容易：
boolean hasMoreResultSets;
try (PreparedStatement stmt = con.prepareStatement(SQL);) {
hasMoreResultSets = stmt.execute();
while (hasMoreResultSets) {
ResultSet rs = stmt.getResultSet();
rs.next();
rs.close();
hasMoreResultSets = stmt.getMoreResults();
}
}
这可以成功编译，但是不起作用。没有异常被抛出。甚至试图通过查看所有结果集来获取异常也不起作用。
所以我提出了多个问题：
如果您想解决这个问题，我已经提供了完整的测试用例。
pom.xml
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>de.thoughtgang.otto</groupId>
<artifactId>sql-server-test</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>jar</packaging>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
<maven.surefire.plugin.version>2.22.1</maven.surefire.plugin.version>
<junit.jupiter.version>5.3.1</junit.jupiter.version>
<junit.platform.version>1.4.0</junit.platform.version>
</properties>
<dependencies>
<dependency>
<groupId>org.junit.jupiter</groupId>
<artifactId>junit-jupiter-api</artifactId>
<version>${junit.jupiter.version}</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.junit.jupiter</groupId>
<artifactId>junit-jupiter-engine</artifactId>
<version>${junit.jupiter.version}</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>com.microsoft.sqlserver</groupId>
<artifactId>mssql-jdbc</artifactId>
<version>7.2.1.jre8</version>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<artifactId>maven-surefire-plugin</artifactId>
<version>${maven.surefire.plugin.version}</version>
</plugin>
</plugins>
</build>
</project>
SQLServerExceptionTest.java
import com.microsoft.sqlserver.jdbc.SQLServerException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import org.junit.jupiter.api.AfterAll;
import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertThrows;
import org.junit.jupiter.api.BeforeAll;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.TestInstance;
import org.junit.jupiter.api.TestInstance.Lifecycle;
@TestInstance(Lifecycle.PER_CLASS)
public class SQLServerExceptionTest {
private static final String URL ="jdbc:sqlserver://localhost;databaseName=master";
private static final String USERNAME = "sa";
private static final String PASSWORD = "MSSQLServer2017";
private static final String SQL = "SELECT 1; INSERT INTO test (test) VALUES (23);";
private Connection con;
@BeforeAll
public void beforeAll() throws ClassNotFoundException, SQLException {
Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
con = DriverManager.getConnection(URL, USERNAME, PASSWORD);
}
@AfterAll
public void afterAll() throws SQLException {
if (con != null && ! con.isClosed()) {
con.close();
}
}
/**
* This unit test will execute the SQL string consisting of multiple statments but
* using a Prepared Statement. It fails to detect the error that occurs because there
* is not table 'test'.
*/
@Test
public void testPreparedStatement() {
SQLServerException sqlex = assertThrows(SQLServerException.class, () -> {
boolean hasMoreResultSets;
try (PreparedStatement stmt = con.prepareStatement(SQL);) {
hasMoreResultSets = stmt.execute();
System.out.println(hasMoreResultSets);
while (hasMoreResultSets) {
System.out.println("Resultset found");
ResultSet rs = stmt.getResultSet();
rs.next();
rs.close();
hasMoreResultSets = stmt.getMoreResults();
}
System.out.println(stmt.getMoreResults());
}
});
assertEquals("Invalid object name 'test'.", sqlex.getMessage());
}
/**
* This unit test will execute the SQL string consisting of multiple statments and
* successfully detect that an error has occured.
*/
@Test
public void testStatement() {
SQLServerException sqlex = assertThrows(SQLServerException.class, () -> {
boolean hasMoreResultSets;
try (Statement stmt = con.createStatement();) {
hasMoreResultSets = stmt.execute(SQL);
System.out.println(hasMoreResultSets);
/* while (hasMoreResultSets) {
System.out.println("Resultset found");
ResultSet rs = stmt.getResultSet();
rs.next();
rs.close();
hasMoreResultSets = stmt.getMoreResults();
}
System.out.println(stmt.getMoreResults()); */
}
});
assertEquals("Invalid object name 'test'.", sqlex.getMessage());
}
}