MySQL MBRContains 语句抛出 MySQLExceptionError

Question

我正在做一个 Java 项目，我们使用它的 sql 库函数从 MySQL 服务器访问和查询。

出现问题的代码是：

String setBox = "SET @box = 
                                'Polygon((" + lx + " " + ry + ","
                                            + rx + " " + ry + ","
                                            + lx + " " + ly + ","
                                            + rx + " " + ly + ","
                                            + lx + " " + ry + "))';\n";

ResultSet regionResult = stmt.executeQuery(setBox + 
  "SELECT ItemID FROM ItemPoint WHERE MBRContains(GeomFromText(@box), Coords);\n");

错误发生在第二条语句(ResultSet regionResult = ...)

我收到的错误是：

"com.mysql.jdbc.exception.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to user near 'SELECT ItemID FROM ItemPoint WHERE MBRContains((GeomFromText(@box), Coords)' at line 2"

我不确定为什么会出现语法错误，因为我是基于它：http://dev.mysql.com/doc/refman/5.5/en/using-spatial-indexes.html。

我的MySQL服务器版本是：5.5.40-0ubuntu0.14.04.1 (Ubuntu)

Answer 1

你的问题不是MySql，是PreparedStatement。你不能用它来运行两个语句，你必须使用 CallableStatement

对于您的问题，它将类似于：

String callString = "{ call SET @box = 'Polygon(( ? ?,
                                       ? ?,
                                       ? ?,
                                       ? ?,
                                       ? ?))'; 
                      SELECT ItemID 
                        FROM ItemPoint 
                       WHERE MBRContains(GeomFromText(@box), Coords); }";

CallableStatement callableStatement = con.prepareCall(callString);
callableStatement.setInt(1, lx);
callableStatement.setInt(2, ry);
callableStatement.setInt(3, rx);
callableStatement.setInt(4, ry);
callableStatement.setInt(5, lx);
callableStatement.setInt(6, ly);
callableStatement.setInt(7, rx);
callableStatement.setInt(8, ly);
callableStatement.setInt(9, lx);
callableStatement.setInt(10, ry);
ResultSet regionResult = callableStatement.executeQuery();

请注意，这可能无法正常工作。你可能需要改变一些东西，这是基本的想法。我是凭记忆做的，所以...

Answer 2

我可以通过这样做来让它工作：

String box = "Polygon((" 
                        + lx + " " + ry + ", "
                        + rx + " " + ry + ", "
                        + rx + " " + ly + ", "
                        + lx + " " + ly + ", "
                        + lx + " " + ry + "))";

ResultSet regionResult = stmt.executeQuery(//setBox + 
  "SELECT ItemID FROM ItemPoint WHERE MBRContains(GeomFromText(' " + box +  " '), Coords);\n");

MySQL MBRContains 语句抛出 MySQLExceptionError

MySQL MBRContains statement throwing MySQLExceptionError

java

mysql

jdbc

spatial-query