javascript - TypeORM 查詢返回空陣列

我正在嘗試從現有的資料庫中檢索數據。我最近從 Expo 管理工作流程切換到了裸工作流程，嘗試用 TypeORM 測試 react-native-sqlite-storage。然而，TypeORM 原生查詢總是返回一個空陣列，我完全不知道為什麼。

這是我的程式碼，它是基於這個範例 https://dev.to/jgabriel1/expo-sqlite-typeorm-4mn8

DictionaryScreen.js

function DictionaryScreen(props) {
    const { ejRepository } = useDatabaseConnection();

    const handleinputWord = async () => {
        console.log(props.inputWord);  //=>this console.logs the text from the input below 
        try {
            const results = await ejRepository.getWordandMean(props.inputWord);
            
            console.log(results); //=> Here I expect an array of the query result but it only returns []

        } catch (error) {
            console.log(error)
        }
    }

    return(
                <View style={styles.searchContainer}>
                    <MaterialCommunityIcons name="text-search" color="white" size={30}/>
                    <TextInput
                        style={styles.input}
                        onChangeText={props.updateTextInput}
                        onSubmitEditing={handleinputWord}
                        value={props.inputWord}
                        placeholder='Look up the word (Type exactly)'
                        keyboardType="default"
                    /> 
                <StatusBar style='light' />
                </View>
           )
}

const mapStateToProps = state => {
    return { 
        inputWord: state.inputWord
    }
};
    
const mapDispatchToProps = {updateTextInput};
    
    
export default connect(mapStateToProps, mapDispatchToProps) (DictionaryScreen);

repository.ts

export class EJRepository {
    private ormRepository: Repository<EJModel>;

    constructor(connection: Connection) {
      this.ormRepository = connection.getRepository(EJModel);
    }

    public async getWordandMean(props: any): Promise<EJModel> {
      console.log(props);  //=> this returns the same text from DictionaryScreen

      const results = await this.ormRepository.query(
        `SELECT * FROM ejmodel WHERE word LIKE '%${props}%';`, [props]);
 
      return results;
    }
}

connection.tsx

interface DatabaseConnectionContextData {
    ejRepository: EJRepository;
}
  
const DatabaseConnectionContext = createContext<DatabaseConnectionContextData>(
    {} as DatabaseConnectionContextData,
  );
  
export const DatabaseConnectionProvider: React.FC = ({ children }) => {
　　　const [connection, setConnection] = useState<Connection | null>(null);
  
　　　const connect = useCallback(async () => {
      　const createdConnection = await createConnection({
        　　type: 'react-native',
        　　name: "ejdict.v1.0",
        　　database: '***.db',
        　　entities: [EJModel],
           location: 'default',
       　　 migrations: [ejdict1621603544180],
        　　migrationsRun: true,
        　　synchronize: false,
           logging: true,
        　　extra: {createFromLocation: '/Users/***/***/ios/***/www/***.db' }
      　});
  
      　setConnection(createdConnection);
    　}, []);
  
    useEffect(() => {
      if (!connection) {
        connect();
      }
    }, [connect, connection]);
  
    if (!connection) {
      return <ActivityIndicator />;
    }
  
return (
  　<DatabaseConnectionContext.Provider
      value={{
        ejRepository: new EJRepository(connection),
      }}
    >
      {children}
    </DatabaseConnectionContext.Provider>
  );
};

export function useDatabaseConnection() {
  const context = useContext(DatabaseConnectionContext);

  return context;
}

EJModel.ts

import {Entity, PrimaryColumn, Column} from "typeorm";

@Entity({name: "ejmodel"})
export class EJModel {

    @PrimaryColumn({type: 'integer'})
    item_id: number;

    @Column({type: 'text'})
    word: string;

    @Column({type: 'text'})
    mean: string;

    @Column({type: 'integer'})
    level: number;
}

附註：在 React Native 專案中嘗試載入現有資料庫是很少見的嗎？幾乎沒有可行的範例。我曾經在 Expo 上讓它運作過，但我發現我需要遷移功能，然後嘗試用 TypeORM 做同樣的事情，結果浪費了很多時間……

答案＃1

我已經按照步驟找到這個問題的解決方法

1. 調整表格的實體至

   @Entity({ name: YOUR_TABLE_NAME, synchronize: false, })

2. 將已有的資料庫放入目錄

   android/app/src/main/assets or android/app/src/main/assets/www

3. Typeorm 聲明

   export const AppDataSource=new DataSource({ type: "react-native", database: database.db, location: "default", synchronize: true, entities: [YOUR_ENTITY], logging: ["error", "query", "schema"], });

//注意，如果你希望所有表格都不同步，可以設為 false，或者像步驟1一樣在每個實體中單獨設置。
4) 在你的 index.android.js 或 App.js 文件中，使用 openDatabase 來連接資料庫。

SQLite.openDatabase(
  {
    name: "database.db",
    createFromLocation: "~database23_02_17.db",
    location: "default",
  },
  () => {
    console.log("db connection success");
  },
  () => {
    console.log("db connection error");
  }
);

5. 如果您已經在實體設備上安裝了該應用程式，請先卸載它（因為應用程式不會更新資料庫檔案），然後再重新執行建置。

   cd android &&./gradlew clean cd .. && react-native run-android