我做了一个省市联动的效果,根据省名查找对应的市的名称代码如下:public String[] getCities(String prov) {
System.out.println("prov name:"+prov);
Connection conn = null;
PreparedStatement pStmt = null;
ResultSet rs = null;
String[] cities = null;
int numbers = 0;
String sql = "select cityname from cityvotes where provname=?";
String sqlGetCount = "SELECT COUNT(*) num FROM cityvotes WHERE provname=?";
try {
conn = JdbcUtils.getConnection();
pStmt = conn.prepareStatement(sqlGetCount);
pStmt.setString(1, prov);
rs = pStmt.executeQuery();
while(rs.next()) {
numbers = rs.getInt("num");
cities = new String[numbers];
}
//System.out.println("The prov "+prov+"has" + numbers + "cities!");
pStmt = conn.prepareStatement(sql);
pStmt.setString(1, prov);
rs = pStmt.executeQuery();
int i = 0;
while(rs.next()) {
cities[i] = rs.getString("cityname");
i = i + 1;
} } catch (SQLException e) {
e.printStackTrace();
} finally {
JdbcUtils.free(rs, pStmt, conn);
}
return cities;
}这段代码访问的是远程数据库,跟踪调试的结果是没有取到数据,但是将sql语句放在SQLYog客户端里面执行能够正常的执行。并且,同一份代码在本机Tomcat(数据库在本地),部署到服务器上却读不到数据。不知道是为什么。麻烦各位指点一下。谢谢!
System.out.println("prov name:"+prov);
Connection conn = null;
PreparedStatement pStmt = null;
ResultSet rs = null;
String[] cities = null;
int numbers = 0;
String sql = "select cityname from cityvotes where provname=?";
String sqlGetCount = "SELECT COUNT(*) num FROM cityvotes WHERE provname=?";
try {
conn = JdbcUtils.getConnection();
pStmt = conn.prepareStatement(sqlGetCount);
pStmt.setString(1, prov);
rs = pStmt.executeQuery();
while(rs.next()) {
numbers = rs.getInt("num");
cities = new String[numbers];
}
//System.out.println("The prov "+prov+"has" + numbers + "cities!");
pStmt = conn.prepareStatement(sql);
pStmt.setString(1, prov);
rs = pStmt.executeQuery();
int i = 0;
while(rs.next()) {
cities[i] = rs.getString("cityname");
i = i + 1;
} } catch (SQLException e) {
e.printStackTrace();
} finally {
JdbcUtils.free(rs, pStmt, conn);
}
return cities;
}这段代码访问的是远程数据库,跟踪调试的结果是没有取到数据,但是将sql语句放在SQLYog客户端里面执行能够正常的执行。并且,同一份代码在本机Tomcat(数据库在本地),部署到服务器上却读不到数据。不知道是为什么。麻烦各位指点一下。谢谢!
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