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          ??一站式輕松地調用各大LLM模型接口，支持GPT4、智譜、豆包、星火、月之暗面及文生圖、文生視頻
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                            ER模型分為：局部概念模型，全局概念模型，模型評審三個過程。從局部到全局，最后由模型評審來評審設計的數據庫是否符合要求。
（1）局部
定義實體，定義聯系，確定屬性，逐一畫出局部ER圖。
（2）全局
確定公共實體，合并局部，消除不一致因素，優化全局。<br/>
ER模型圖有三個部分組成，如下圖：
![](https://img.kancloud.cn/c3/b6/c3b66afd9692c6a7e27a6beb959a59e2_754x344.png)
它們之間的用→連接：
![](https://img.kancloud.cn/7c/0e/7c0e58b67d5c63d0480c434b751f5a82_729x526.png)
                    
                
        
                
            
        
                
    
                
    
                
        
                
    
                

                







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