java - 如何比较从java到mysql的日期

Question

嗨，我想知道我们如何将 java 中的当前日期与 mysql 中存储的日期进行比较。

存储在 MySQL 中的日期是2013-01-04 13:15:00

当我通过获取当前日期在java中比较这个日期时

Date date = new Date();

然后写一个查询，如果存储在 MySQL 中的日期小于当前显示结果。但查询返回 0 结果。

select model from abc model where model.abcStartDate >= date and model.abcEndDate >= date

在 MySQL 中，开始日期和结束日期都是时间戳数据类型。

下面是EJB实体类

@Entity
@Table(name = "abc_table", uniqueConstraints = {})
public class ABCClass implements java.io.Serializable {

private static final long serialVersionUID = -1924961655993587546L;

// Fields
private Date abcStartDate;
private Date abcEndDate;

// Constructors

/** default constructor */
public ABCClass() {
}


@OrderBy(value="3")
@Temporal(TemporalType.TIMESTAMP)
@Column(name = "abc_start_date", unique = false, nullable = false, insertable = true, updatable = true, length = 19)
public Date getabcStartDate() {
    return this.abcStartDate;
}

public void setabcStartDate(Date abcStartDate) {
    this.abcStartDate = abcStartDate;
}

@OrderBy(value="4")
@Temporal(TemporalType.TIMESTAMP)
@Column(name = "abc_end_date", unique = false, nullable = false, insertable = true, updatable = true, length = 19)
public Date getabcEndDate() {
    return this.abcEndDate;
}

public void setabcEndDate(Date abcEndDate) {
    this.abcEndDate = abcEndDate;
}

}

Answer 1

One of right approach - use parametrized query in java Use prepared statement with query

select model from abc model where model.abcStartDate <= ? and model.abcEndDate >= ?

And then set first and second params to new Date() in your java code. In this case you can compare not only current date, but any java Date you have

Answer 2

如果要使用PreparedStatement比较 SQL 查询中的日期：

String query="select model from abc model where model.abcStartDate >= ? and model.abcEndDate <=?;";
PreparedStatement stmnt = conn.preparedStatement(query);
stmnt.setTimestamp(1, new java.sql.Timestamp(Calender.getInstance().getTime()));
stmnt.setTimestamp(2, new java.sql.Timestamp(Calender.getInstance().getTime()));
stmnt.executeQuery();

Answer 3

您必须将日期与时间进行比较：
将 java.sql.Timestamp 用于 util.Date。它会为它工作。
例如：
java.sql.Timestamp t = new Timestamp(Date.getTime());