英文:
change boolean value Spring Data JPA
问题
我正在编写一段简单的代码，在这段代码中，我需要在数据库表中更改布尔值，而不是删除整行数据。我用注释标记了适当的字段：
@Column(name = "exist", columnDefinition = "boolean default true")
但是，当我在数据库中保存一个新实例时，它没有标记为true/false。然后我直接在字段中设置了默认值：
private Boolean exist = true;
它开始标记我的实例，但是当我尝试更改值时，在两种情况下都不起作用（在第一种情况下，我无法将null更改为false，在第二种情况下，无法将true更改为false）。
我使用的是PostgreSQL数据库，我从官方文档中获取了解决方案Default Column Values in JPA。
我的实体类：
private long id;
private String colour;
private Boolean exist = true;
public Colour() {
}
@Id
@Column(name = "id", nullable = false, unique = true)
@GeneratedValue(strategy = GenerationType.IDENTITY)
public long getId() {
return id;
}
@Column(name = "colour", unique = true)
public String getColour() {
return colour;
}
@Column(name = "exist", columnDefinition = "boolean default true")
public Boolean getExist() {
return exist;
}
public void setId(long id) {
this.id = id;
}
public void setColour(String colour) {
this.colour = colour;
}
public void setExist(Boolean exist) {
this.exist = exist;
}
我的删除方法：
@Override
public void deleteColour(long id) {
Colour colour = getOne(id);
try {
colour.setExist(false);
colourRepository.save(colour);
} catch (NullPointerException e) {
System.out.println("delete is not possible: colour doesn't exist");
}
}
运行deleteColour()方法后的"colours"表格：使用注释的情况
运行deleteColour()方法后的"colours"表格：使用字段默认值的情况
谢谢您的时间！
英文:
I'm writing a simple code, where I need to change a boolean value instead delete whole row in my table in data base. I marked appropriate field with annotation:
" columnDefinition = " boolean default true ",
but when i saved a new instance in data base, it hasn't mark true/false on it. Then I put default value direct in field: " private Boolean exist = true; "
it start marking my instances, but when i try to change the value, it isn't work in both cases. (in first case I can't change null to false, in second case true to false)
I use PostgreSQL, I took my solution from official documentation Default Column Values in JPA
my entity class:
private long id;
private String colour;
private Boolean exist = true;
public Colour() {
}
@Id
@Column(name = "id", nullable = false, unique = true)
@GeneratedValue(strategy = GenerationType.IDENTITY)
public long getId() {
return id;
}
@Column(name = "colour", unique = true)
public String getColour() {
return colour;
}
@Column(name = "exist", columnDefinition = "boolean default true")
public Boolean getExist() {
return exist;
}
public void setId(long id) {
this.id = id;
}
public void setColour(String colour) {
this.colour = colour;
}
public void setExist(Boolean exist) {
exist = exist;
}
my delete method:
@Override
public void deleteColour(long id) {
Colour colour = getOne(id);
try {
colour.setExist(false);
colourRepository.save(colour);
} catch (NullPointerException e) {
System.out.println("delete is not possible: colour doesn't exist");
}
}
table "colours" after running method deleteColour(): in case of annotation
table "colours" after running method deleteColour(): in case of field default
thank you for your time!
专注分享java语言的经验与见解，让所有开发者获益！
评论