MySQL日期值不正确:null

Question

我正在尝试从Java应用程序更新表,其中某个列可能为NULL.我尝试了几种不同的方法,但我总是得到以下错误:

com.mysql.jdbc.MysqlDataTruncation: Data truncation: Incorrect date value: 'null' for column 'scheidingsdatum' at row 1

我确保该表允许scheidingsdatum字段的NULL值,并且可以在直接插入MySQL时插入NULL值

这是PHPMyAdmin中的表结构:

这些表使用innoDB

我尝试了以下解决方案:

1:只需在参数中使用NULL变量

stmnt = conn.prepareStatement("UPDATE gezinnen SET "
                            + "ouder1 = ?," 
                            + "ouder2 = ?," 
                            + "huwelijksdatum = ?,"
                            + "scheidingsdatum = ? "
                            + "WHERE gezinsNummer = ?");

stmnt.setString(1, ouder1);
stmnt.setString(2, ouder2);
stmnt.setString(3, huwelijksdatum);
stmnt.setString(4, scheidingsdatum);
stmnt.setString(5, nummer);

2:查询中的硬编码NULL(if/else块内)

stmnt = conn.prepareStatement("UPDATE gezinnen SET "
                            + "ouder1 = ?," 
                            + "ouder2 = ?," 
                            + "huwelijksdatum = ?,"
                            + "scheidingsdatum = NULL "
                            + "WHERE gezinsNummer = ?");

stmnt.setString(1, ouder1);
stmnt.setString(2, ouder2);
stmnt.setString(3, huwelijksdatum);
stmnt.setString(4, nummer);

3:使用setNull(4,java.sql.Types.DATE)

stmnt = conn.prepareStatement("UPDATE gezinnen SET "
                            + "ouder1 = ?," 
                            + "ouder2 = ?," 
                            + "huwelijksdatum = ?,"
                            + "scheidingsdatum = ? "
                            + "WHERE gezinsNummer = ?");

stmnt.setString(1, ouder1);
stmnt.setString(2, ouder2);
stmnt.setString(3, huwelijksdatum);
stmnt.setNull(4, java.sql.Types.DATE);
stmnt.setString(5, nummer);

4:使用setNull(4,java.sql.Types.NULL)

stmnt = conn.prepareStatement("UPDATE gezinnen SET "
                            + "ouder1 = ?," 
                            + "ouder2 = ?," 
                            + "huwelijksdatum = ?,"
                            + "scheidingsdatum = ? "
                            + "WHERE gezinsNummer = ?");

stmnt.setString(1, ouder1);
stmnt.setString(2, ouder2);
stmnt.setString(3, huwelijksdatum);
stmnt.setNull(4, java.sql.Types.NULL);
stmnt.setString(5, nummer);

以下是我的database.properties文件和连接创建:

database.properties

jdbc.drivers=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://IP:3306/TABLE_NAME
jdbc.username=USER
jdbc.password=PASSWORD

连接创建

Class.forName(props.getProperty("jdbc.drivers")).newInstance();
this.conn = (Connection) DriverManager.getConnection(props.getProperty("jdbc.url"),props.getProperty("jdbc.username"),props.getProperty("jdbc.password"));

Answer 1

我刚刚做了一个测试，它对我有用stmnt.setNull(4, java.sql.Types.Date);，您确定 stmnt.setString(3, huwelijksdatum);huwelijksdatum 的值是有效的 mysql 日期字符串而不是“null”吗？