Column注解的columnDefinition用法

本文深入探讨了ORM框架中columnDefinition属性的作用与应用,解析如何通过此属性指定字段类型、长度、约束及默认值,适用于通过实体类自动生成数据库表结构的场景。

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columnDefinition属性表示创建表时,该字段创建的SQL语句,一般用于通过Entity生成表定义时使用,如果数据库中表已经建好,该属性没有必要使用

1、指定字段类型、长度、是否允许null、是否唯一、默认值

/** 仓库编号 */
@Column(name = "code",columnDefinition = "Varchar(100) not null default'' unique")
private String code;

2、需要特殊指定字段类型的情况

@Column(name = "remark",columnDefinition="text")
private String remark;
@Column(name = "salary", columnDefinition = "decimal(5,2)")
private BigDecimal salary;
@Column(name="birthday",columnDefinition="date")
private Date birthday;
@Column(name="createTime",columnDefinition="datetime")
private Date createTime;

 

package indi.backend.repository.entity; import jakarta.persistence.*; import lombok.AllArgsConstructor; import lombok.Builder; import lombok.Data; import lombok.NoArgsConstructor; import java.util.Date; import java.util.UUID; @Data @Builder @NoArgsConstructor @AllArgsConstructor @Entity @Table(name = "Users") public class Users { @Id @Column(columnDefinition = "uniqueidentifier") public UUID id; @Column(columnDefinition = "datetime2") public Date creationTime; @Column(columnDefinition = "nvarchar(max)") public String account; @Column(columnDefinition = "nvarchar(max)") public String password; @Column(columnDefinition = "bit") public Boolean enabled; @Column(columnDefinition = "datetime2") public Date lockStartTime; @Column(columnDefinition = "datetime2") public Date lockEndTime; @Column(columnDefinition = "nvarchar(max)") public String username; @Column(columnDefinition = "nvarchar(max)") public String avatar; @Column(columnDefinition = "nvarchar(max)") public String email; @Column(columnDefinition = "nvarchar(max)") public String phone; @Column(columnDefinition = "nvarchar(max)") public String sex; @Column(columnDefinition = "datetime2") public Date birthday; @Column(columnDefinition = "nvarchar(max)") public String address; @Column(columnDefinition = "datetime2") public Date lastActiveTime; @Column(columnDefinition = "int") public Integer permissionsLevel; @OneToOne(mappedBy = "user", cascade = CascadeType.ALL) private TokenPool tokenPool; } package indi.backend.repository.entity; import jakarta.persistence.*; import lombok.AllArgsConstructor; import lombok.Builder; import lombok.Data; import lombok.NoArgsConstructor; import java.util.Date; import java.util.UUID; @Data @Builder @NoArgsConstructor @AllArgsConstructor @Entity @Table(name = "TokenPool") public class TokenPool { @Id @Column(columnDefinition = "uniqueidentifier") public UUID id; @Column(columnDefinition = "datetime2") public Date creationTime; @Column(columnDefinition = "datetime2") public Date expiredTime; @Column(columnDefinition = "bit") public Boolean longTerm; @OneToOne @JoinColumn(name = "userId", nullable = false) private Users user; } 根据这两个实体优化public String login(String account, String password) { Users users = usersRepository.findByAccountAndPassword(account, cryptoUtil.sha256(password)).orElseThrow(() -> new RuntimeException("用户名或密码错误")); Date expiredTime = Date.from(LocalDateTime.now().plusSeconds(3600).atZone(ZoneId.systemDefault()).toInstant()); users.setLastActiveTime(expiredTime); usersRepository.save(users); TokenPool tokenPool = tokenPoolRepository.findByUserId(users.getId()).orElseGet(() -> TokenPool.builder().id(UUID.randomUUID()).creationTime(new Date()).longTerm(false).user(users).build()); tokenPool.setExpiredTime(expiredTime); tokenPoolRepository.save(tokenPool); return tokenPool.getId().toString(); } public void logout(String token) { if (token == null || token.isEmpty()) { throw new RuntimeException("没有传入token"); } TokenPool tokenPool = tokenPoolRepository.findById(UUID.fromString(token)).orElse(null); if (tokenPool != null) { usersRepository.findById(tokenPool.getUser().getId()).ifPresent(users -> { users.setLastActiveTime(new Date()); usersRepository.save(users); }); tokenPoolRepository.delete(tokenPool); } }不抽取方法
03-22
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