Grails的/格姆映射非標準-命名外鍵

Question

我有一個存儲的代理層次結構的表：

create table agent (
    agent_id int not null, 
    agent_name varchar(255), 
    agent_parent_id, 
    constraint pk_agent primary key (agent_id)); 

alter table agent 
    add constraint fk_agent_agent foreign key (agent_parent_id) references (agent_id); 

我仿照它：

class Agent { 
    String agentName 
    Agent agentParent 
    static mapping = { 
    id column: 'agent_id' 
    id generator: 'sequence', params: [sequence: 'agent_id_seq'] 
    } 
} 

每劑可有許多特性：

create table agent_property (
    agent_property_id int not null, 
    agent_property_name varchar(255), 
    agent_id int, 
    constraint pk_agent_property primary key (agent_property_id)); 

alter table agent_property (
    add constraint fk_agent_property_agent foreign key (agent_id) references agent(agent_id); 

我建模，作爲：

class AgentProperty { 
    String agentPropertyName 
    static hasOne = [agent: Agent] 
    static mapping = { 
    id column: 'agent_property_id' 
    id generator: 'sequence', params: [sequence: 'agent_property_id_seq'] 
    } 
} 

我創建了一個視圖輕鬆查看代理商的層次結構：

create view pathogen as 
    select c.agent_id as id, a.agent_name as genus, b.agent_name as species, c.agent_name as strain, d.agent_name as toxin 
    from agent a 
    left join agent b on a.agent_id = b.agent_parent_id 
    left join agent c on b.agent_id = c.agent_parent_id 
    left join agent d on c.agent_id = d.agent_parent_id 
    where a.agent_parent_id is null; 

我的問題是在模擬病原體視圖。我已經這樣做了：

class Pathogen { 
    String genus 
    String species 
    String strain 
    String toxin 
    static hasMany = [agentProperties: AgentProperty] 
} 

這意味着agent_property表中有一個外鍵'pathogen_id'。但事實並非如此。 外鍵是agent_id。 我想AgentProperty涉及到病菌對AGENT_ID好像有約束：

alter table agent_propery 
    add constraint fk_agent_property_pathogen foreign key (agent_id) references pathogen (id); 

我試圖暗示財產agentProperties映射在我的Pathgeon類AGENT_ID，是這樣的：

static mapping = { 
    agentProperties column: agent_id // or AgentProperty.agent 
} 

但那沒用。

我該如何告訴GORM使用agent_property.agent_id作爲外鍵？

Answer 1

解決我最初的問題是我沒有把agent_id放在引號中。

agentProperties column: 'agent_id' 

這現在工作：

class Pathogen { 
    String genus 
    String species 
    String strain 
    String toxin 

    static hasMany = [agentProperties: AgentProperty] 

    static mapping = { 
    // use agent_id to releate to AgentProperty 
    agentProperties column: 'agent_id' 
    } 
} 

class AgentProperty { 
    String agentPropertyName 

    static belongsTo = [agent: Agent] 
    static hasOne = [pathogen: Pathogen] 

    static mapping = { 
    id column: 'agent_property_id' 
    id generator: 'sequence', params: [sequence: 'agent_property_id_seq'] 
    // use agent_id to relate to Pathogen 
    pathogen column: 'agent_id', insertable: false, updateable: false 
    } 
} 

Answer 2

你的域類需要修改的點點粘到你的數據庫有設計，

class Agent { 
    String agentName 
    Agent agentParent 

    //agent_id Foreign Key to AgentProperty. Agent has many AgentProperties 
    static hasMany = [agentProperties: AgentProperty] 

    static mapping = { 
    id column: 'agent_id' 
    id generator: 'sequence', params: [sequence: 'agent_id_seq'] 
    } 
} 

class AgentProperty { 
    String agentPropertyName 

    //AgentProperty belongs to an Agent. Cascade delete is enabled 
    static belongsTo = [agent: Agent] 
    static mapping = { 
    id column: 'agent_property_id' 
    id generator: 'sequence', params: [sequence: 'agent_property_id_seq'] 
    } 
} 

class Pathogen { 
    String genus 
    String species 
    String strain 
    String toxin 

    //like foreign key pathogen_id in agent table 
    static hasMany = [agents: Agent] 
} 

您可以從Pathogen通過Agent得到AgentProperty舉行。

如果我正確地讀你的問題，那麼這就是你需要的。

Pathogen hasMany Agents 
Agent hasMany AgentProperty