Oracle Database --- Yelp Data Analysis Application

Overview
- Basic Info
- Functionality
- - 初始GUI
  - Simple Business Search
  - Simple User Search
  - 筛选review
  - OR AND
Implementation
- JSON files --- source data
- create.db --- create tables
- Populate.Java --- populate data
- - JDBC connection
  - 从JSON文件提取数据
- hw3.java --- GUI + SQL query
- - 构建GUI
  - - 声明swing组件
    - 初始化GUI
  - Business Query
  - - display Main Category
    - search with main category
    - search with sub category
    - search with attributes
    - common part for building all SQL queries
  - User Query
  - Review Query
Notes

Overview Basic Info

使用点评网站 Yelp.com 发布的 Yelp Dataset Challenge里的data，开发一个数据筛选软件
tech stack: Java Swing + JDBC + Oracle database 11g
数据量: business: 2万, reviews: 80万, users: 21万

Functionality 初始GUI

Simple Business Search

选择main category 筛选出对应sub category, 选择sub category筛选出对应 attributes

点击execute business search显示符合条件的business

sub-category和attributes是optional的, 也就是不选择subCategory和attribute也可以查询business

在result中点击一条business，可以显示出给这个business点评过的所有用户
点击一个写过点评的用户可以显示出点评内容

Simple User Search

可以根据注册日期, Review Count的数量, 好友数量, 评价打分，投票数筛选用户

点击Execute User Search显示查找结果，点击一个用户显示此用户的所有点评，点击一条点评显示具体内容

筛选review

在review栏中添加筛选条件，可以筛选review (这个用户之前有6个review，现在只有一个了
同样可以筛选business 的review

这个business之前有很多review现在只有三条

OR AND

business search 和 user search有AND和OR属性
business search: 表示main category, sub category, attributes之间是and关系或者or关系
user search: 表示user search的各个条件是and或者or关系

Implementation JSON files — source data

business.json

user.json

review.json

create.db — create tables

CREATE TABLE BUSINESS (
    business_id VARCHAR(25) PRIMARY KEY,
    full_address VARCHAR(200) NOT NULL,
	ifOpen  VARCHAR(5),
	city VARCHAR(50) NOT NULL,
	state_name VARCHAR(20) NOT NULL,
	review_count NUMBER,
	business_name VARCHAR(100) NOT NULL,
	starts NUMBER
);

CREATE TABLE BUSINESS_MAIN_CATEGORIES(
	business_id VARCHAR(25),
	main_category VARCHAR(50),
	PRIMARY KEY (business_id, main_category),
	FOREIGN KEY(business_id) REFERENCES BUSINESS(business_id)
);

CREATE TABLE BUSINESS_SUB_CATEGORIES (
	business_id VARCHAR(25),
	sub_category VARCHAR(50),
	PRIMARY KEY (business_id, sub_category),
	FOREIGN KEY(business_id) REFERENCES BUSINESS(business_id)
);

CREATE TABLE BUSINESS_ATTRIBUTES (
	business_id VARCHAR(25),
	attributes VARCHAR(50),
	PRIMARY KEY (business_id, attributes),
	FOREIGN KEY(business_id) REFERENCES BUSINESS(business_id)
);

CREATE TABLE YELP_USERS ( 
	yelping_since DATE,
	num_votes NUMBER,
	review_count NUMBER,
	user_name VARCHAR(100),
	user_id VARCHAR(25) PRIMARY KEY,
	average_stars NUMBER,
	numFriend NUMBER
);

CREATE TABLE REVIEW (
	num_votes NUMBER,
	user_id VARCHAR(25) NOT NULL,
	review_id VARCHAR(25) PRIMARY KEY,
	stars NUMBER,
	review_date DATE,
	review_text Long,
	business_id VARCHAR(25) NOT NULL,
	FOREIGN KEY(business_id) REFERENCES BUSINESS(business_id),
	FOREIGN KEY(user_id) REFERENCES YELP_USERS(user_id)
);

Populate.Java — populate data

JDBC connection

从JSON文件提取数据

使用simpleJson — import org.json.simple.

Example: review.json

  				//transform every line of input to json object
                JSONParser parser = new JSONParser();
                JSONObject jsonObject = (JSONObject) parser.parse(line);

                //retrieve json values from the first layer of the json object
                String text = (String) jsonObject.get("text");
                String user_id = (String) jsonObject.get("user_id");
                String review_id = (String) jsonObject.get("review_id");

                //get stars
                long stars = (long)jsonObject.get("stars");

                //get date
                String date_string = (String) jsonObject.get("date");
                SimpleDateFormat sdf1 = new SimpleDateFormat("yyyy-MM-dd");
                java.util.Date javaDate = sdf1.parse(date_string);
                java.sql.Date sqlDate = new java.sql.Date(javaDate.getTime());

                //get business id
                String business_id = (String) jsonObject.get("business_id");

                // get votes
                JSONObject votes = (JSONObject) jsonObject.get("votes");
                long funny = (long) votes.get("funny");
                long useful = (long) votes.get("useful");
                long cool = (long) votes.get("cool");
                long numVotes = funny + useful + cool;

hw3.java — GUI + SQL query 构建GUI 声明swing组件

Example:

    ///main panel/
    private JPanel mainPanel = new JPanel();

    ///under main panel///
    //business panel
    private JPanel businessPanel = new JPanel();
    private JLabel businessLabel = new JLabel();
    //review panel
    private JPanel reviewPanel = new JPanel();
    private JLabel reviewLabel = new JLabel();
    /user panel
    private JPanel userPanel = new JPanel();
    private JLabel userLabel = new JLabel();
    /result panel
    private JPanel resultPanel = new JPanel();
    private JLabel resultLabel = new JLabel();

初始化GUI

//set the frame
setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
setResizable(false);
setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
setResizable(false);

///main panel
mainPanel.setBackground(new Color(0, 255, 255
mainPanel.setPreferredSize(new Dimension(1300, 900));
mainPanel.setLayout(new GridLayout(2, 2)); //divide the window with four equal parts

businessPanel(); 
reviewPanel();
userPanel();
resultPanel();

Business Query

使用HashSet储存选择的main category, sub category,attributes和查询出来的main category, sub category,attributes

 private HashSet queriedMainCat = new HashSet<>();
 private HashSet selectedMainCat = new HashSet<>();
 private HashSet queriedSubCat = new HashSet<>();
 private HashSet selectedSubCat = new HashSet<>();
 private HashSet queriedAttributes = new HashSet<>();
 private HashSet selectedAttributes = new HashSet<>();

display Main Category

打开app后显示固定的Main Category, 需要的SQL查询如下:

SELECT DISTINCT main_category, business_id
FROM BUSINESS_MAIN_CATEGORIES

private void initMainCat()  {
        selectedMainCat.clear();

        StringBuilder sqlQuery = new StringBuilder();
        sqlQuery.append("SELECT DISTINCT main_category, business_id").append("n")
                .append("FROM BUSINESS_MAIN_CATEGORIESn");

        System.out.println("---------Prepare SQL query for main categories--------");
        System.out.println(sqlQuery);

        try(Connection connection = getConnection()) {
            //get all the main categories
            PreparedStatement queryMainCategoryStm = connection.prepareStatement(sqlQuery.toString());
            ResultSet results = queryMainCategoryStm.executeQuery();
            System.out.println("---------SQL query send--------");

            //add main categories to  queriedMainCat
            while (results.next()) {
                queriedMainCat.add(results.getString("main_category"));
            }

        } catch (SQLException throwables) {
            throwables.printStackTrace();
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        }

        //display all the main categories and keep records of selected main categories
        updateCategoryScreen(mainCategoryListPanel, queriedMainCat, selectedMainCat);
        System.out.println("---------Display main categories--------n");

        //listener for clicking the select button
        mainSelectButton.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                searchWithMainCat("select");
            }
        });
    }

search with main category

上图点击select会发出

SELECT DISTINCT sub_category
FROM BUSINESS_SUB_CATEGORIES b
WHERe b.business_id in (
	SELECt DISTINCT business_id 
	FROM BUSINESS_MAIN_CATEGORIES t
	WHERe t.main_category in ('Convenience Stores', 'Dentists')
	GROUP BY business_id
	HAVINg COUNT(business_id) = 2
)

上图点击execute business search会发出

SELECt b.business_name, b.business_id, b.state_name, b.city, b.starts
FROM business b
WHERe b.business_id in (
	SELECt DISTINCT business_id 
	FROM BUSINESS_MAIN_CATEGORIES t
	WHERe t.main_category in ('Convenience Stores', 'Dentists')
	GROUP BY business_id
	HAVINg COUNT(business_id) = 2
)

Implementation

private void searchWithMainCat(String clickType) {
        if (businessSearchComboBox.getSelectedItem() == "Choose AND or OR for the search") {
            JOptionPane.showMessageDialog(null, "Please select an operation: AND, OR");
            return;
        }

        queriedSubCat.clear();
        subCategoryListPanel.removeAll();

        StringBuilder sqlQuery = new StringBuilder();
        searchWithMainCategorySQL(sqlQuery, clickType);

        try(Connection connection = getConnection()) {

            Statement queryUserStm = connection.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,
                    ResultSet.CONCUR_READ_ONLY);
            ResultSet results = queryUserStm.executeQuery(sqlQuery.toString());

            if (clickType == "execute") {
                String[] columns = new String[]{"Business_name", "Business_id", "State_name", "City", "Stars"};
                displayResults(results, columns, resultTableForBusiness, extraPanelForResult, "business");
            }
            else {
                while (results.next()) {
                    String subCategory = results.getString("sub_category");
                    queriedSubCat.add(subCategory);
                }
            }
        } catch (SQLException throwables) {
            throwables.printStackTrace();
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        }


        //display all the sub categories and keep records of selected sub categories
        updateCategoryScreen(subCategoryListPanel, queriedSubCat, selectedSubCat);
        System.out.println("---------Display sub categories--------");

        //listener for subSelectButton
        subSelectButton.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                searchWithSubCat("select");
            }
        });

    }

 private void searchWithMainCategorySQL(StringBuilder sqlQuery, String clickType) {
        if (clickType == "execute") {
            sqlQuery.append("SELECT b.business_name, b.business_id, b.state_name, b.city, b.startsn")
                    .append("FROM business b").append("n");
        }
        else if (clickType == "select") {
            selectedSubCat.clear();
            selectedAttributes.clear();
            System.out.println("selected sub category cleared");
            System.out.println("selected attributes clearedn");

            sqlQuery.append("SELECT DISTINCT sub_categoryn")
                    .append("FROM BUSINESS_SUB_CATEGORIES b").append("n");
        }

        sqlQuery.append("WHERe b.business_id in (n");
        sqlTemplate(sqlQuery, "mainCategory", selectedMainCat);
        sqlQuery.append("n)");

        System.out.println(sqlQuery);
        System.out.println("---------SQL query send--------" + "n");
    }

search with sub category

上图点击select会发出

SELECT DISTINCT attributes
FROM BUSINESS_ATTRIBUTES b
WHERe b.business_id in (
	SELECt DISTINCT business_id 
	FROM BUSINESS_MAIN_CATEGORIES t
	WHERe t.main_category in ('Convenience Stores', 'Dentists')

 	INTERSECT 
 	
	SELECt DISTINCT business_id 
	FROM BUSINESS_SUB_CATEGORIES t
	WHERe t.sub_category in ('Day Spas', 'Cosmetic Dentists', 'Endodontists')
)

上图点击execute business search会发出

SELECt b.business_name, b.business_id, b.state_name, b.city, b.starts
FROM business b
WHERe b.business_id in (
	SELECt DISTINCT business_id 
	FROM BUSINESS_MAIN_CATEGORIES t
	WHERe t.main_category in ('Convenience Stores', 'Dentists')

 	INTERSECT 
 	
	SELECt DISTINCT business_id 
	FROM BUSINESS_SUB_CATEGORIES t
	WHERe t.sub_category in ('Day Spas', 'Cosmetic Dentists', 'Endodontists')
)

Implementation

private void searchWithSubCat(String clickType) {
        queriedAttributes.clear();
        attributeListPanel.removeAll();
        StringBuilder sqlQuery = new StringBuilder();

        searchWithSubCategorySQL(sqlQuery, clickType);

        System.out.println(sqlQuery.toString());

        try(Connection connection = getConnection()) {

            Statement queryUserStm = connection.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,
                    ResultSet.CONCUR_READ_ONLY);
            ResultSet results = queryUserStm.executeQuery(sqlQuery.toString());

            System.out.println("---------SQL query send--------");

            if (clickType == "execute") {
                String[] columns = new String[]{"Business_name", "Business_id", "State_name", "City", "Stars"};
                displayResults(results, columns, resultTableForBusiness, extraPanelForResult, "business");
            }
            else {
                while (results.next()) {
                    String attributes = results.getString("attributes");
                    queriedAttributes.add(attributes);
                }
            }
        } catch (SQLException throwables) {
            throwables.printStackTrace();
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        }

        //display all the attributes and keep records of selected attributes
        updateCategoryScreen(attributeListPanel, queriedAttributes, selectedAttributes);
    }

 private void searchWithSubCategorySQL (StringBuilder sqlQuery, String clickType) {
        if (clickType == "execute") {
            sqlQuery.append("SELECT b.business_name, b.business_id, b.state_name, b.city, b.startsn")
                    .append("FROM business b").append("n");
        }
        else if (clickType == "select") {
            selectedAttributes.clear();
            System.out.println("selected attributes clearedn");
            sqlQuery.append("SELECT DISTINCT attributesn")
                    .append("FROM BUSINESS_ATTRIBUTES b").append("n");
        }

        sqlQuery.append("WHERe b.business_id in (n");
        sqlTemplate(sqlQuery, "mainCategory", selectedMainCat);
        sqlQuery.append("n INTERSECT n");
        sqlTemplate(sqlQuery, "subCategory", selectedSubCat);
        sqlQuery.append("n)");

        System.out.println(sqlQuery);
        System.out.println("---------SQL query send--------" + "n");
    }

search with attributes

上图点击execute business search会发出

SELECT b.business_name, b.business_id, b.state_name, b.city, b.starts
FROM business b
WHERe b.business_id in (
	SELECt DISTINCT business_id 
	FROM BUSINESS_MAIN_CATEGORIES t
	WHERe t.main_category in ('Convenience Stores', 'Dentists')
	GROUP BY business_id
	HAVINg COUNT(business_id) = 2
	
	 INTERSECT 
	 
	SELECt DISTINCT business_id 
	FROM BUSINESS_SUB_CATEGORIES t
	WHERe t.sub_category in ('Day Spas', 'Cosmetic Dentists', 'Endodontists')
	GROUP BY business_id
	HAVINg COUNT(business_id) = 3
	
	 INTERSECT 
	 
	SELECt DISTINCT business_id 
	FROM BUSINESS_ATTRIBUTES t
	WHERe t.attributes in ('Parking_lot_false', 'Parking_validated_false', 'Parking_street_false')
	GROUP BY business_id
	HAVINg COUNT(business_id) = 3
)

Implementation

private void searchWithAttribute(String clickType) {
        StringBuilder sqlQuery = new StringBuilder();
        searchWithAttributesSQL(sqlQuery, clickType);

        try (Connection connection = getConnection()) {
            Statement queryUserStm = connection.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,
                    ResultSet.CONCUR_READ_ONLY);
            ResultSet results = queryUserStm.executeQuery(sqlQuery.toString());

            String[] columns = new String[]{"Business_name", "Business_id", "State_name", "City", "Stars"};
            displayResults(results, columns, resultTableForBusiness, extraPanelForResult, "business");

        } catch (SQLException throwables) {
            throwables.printStackTrace();
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        }

    }

private void searchWithAttributesSQL(StringBuilder sqlQuery, String clickType) {
        if (clickType == "execute") {
            sqlQuery.append("SELECt b.business_name, b.business_id, b.state_name, b.city, b.startsn")
                    .append("FROM business b").append("n");
        }

        sqlQuery.append("WHERe b.business_id in (n");
        sqlTemplate(sqlQuery, "mainCategory", selectedMainCat);
        sqlQuery.append("n INTERSECT n");
        sqlTemplate(sqlQuery, "subCategory", selectedSubCat);
        sqlQuery.append("n INTERSECT n");
        sqlTemplate(sqlQuery, "attributes", selectedAttributes);
        sqlQuery.append("n)");

        System.out.println(sqlQuery);
        System.out.println("---------SQL query send--------" + "n");
    }

common part for building all SQL queries

private void sqlTemplate(StringBuilder sqlQuery, String filterType, HashSet selectedItems) {
        String tableName = "";
        String elementName = "";

        if (filterType == "mainCategory") {
            tableName = "BUSINESS_MAIN_CATEGORIES t";
            elementName = "main_category";
        }
        else if (filterType == "subCategory") {
            tableName = "BUSINESS_SUB_CATEGORIES t";
            elementName = "sub_category";
        }
        else if (filterType == "attributes") {
            tableName = "BUSINESS_ATTRIBUTES t";
            elementName = "attributes";
        }

        Iterator it = selectedItems.iterator();
        StringBuilder selectedItemString = new StringBuilder();
        while (it.hasNext()) {
            String item = it.next().toString();
            item = item.replace("'", "''");
            if (it.hasNext()) {
                selectedItemString.append("'").append(item).append("'").append(",").append(" ");
            }
            else {
                selectedItemString.append("'").append(item).append("'");
            }
        }

        int count = selectedItems.size();

        sqlQuery.append("SELECT DISTINCT business_id n");
        sqlQuery.append("FROM ").append(tableName).append("n");
        sqlQuery.append("WHERe ").append("t.").append(elementName).append(" in ")
                .append("(");
        sqlQuery.append(selectedItemString.toString());
        sqlQuery.append(")n");

        if (businessSearchComboBox.getSelectedItem() == "AND") {
            sqlQuery.append("GROUP BY business_idn");
            sqlQuery.append("HAVINg COUNT(business_id) = ").append(String.valueOf(count));
        }
    }

User Query

点击Execute User Search会发出

SELECT *
FROM YELP_USERS
WHERe  review_count >10
OR numFriend <100
OR average_stars >2
OR num_votes >10

Implementation

 private void userSearch() {
        String userLogicOperator = userSearchComboBox.getSelectedItem().toString();

        String memberSince = memberSinceTextField.getText();

        String reviewCntOperator = reviewCntComboBox.getSelectedItem().toString();
        String reviewCntValue = reviewCntTextField.getText();

        String numFriendOpertor = numFriendsComboBox.getSelectedItem().toString();
        String numFriendsValue = numFriendsTextField.getText();

        String avgStarsOperator = avgStarsComboBox.getSelectedItem().toString();
        String avgStarValue = avgStarsTextField.getText();

        String numVotesOperator = numVotesComboBox.getSelectedItem().toString();
        String numVotesValue = numVotesTextField.getText();

        StringBuilder sqlQuery = new StringBuilder();
        sqlQuery.append("SELECT *").append("n")
                .append("FROM YELP_USERS").append("n");

        boolean firstCondition = true;

        if (isValidDate(memberSince)) {
            ifFirstCondition(firstCondition, sqlQuery, userLogicOperator);

            sqlQuery.append("yelping_since").append(" >= ").append("TO_DATE('").append(memberSince).append("','")
                    .append("YYYY-MM-DD')")
                    .append("n");

            firstCondition = false;
        }
        if (reviewCntOperator != "=, >, <" && isValidNumber(reviewCntValue)) {
            ifFirstCondition(firstCondition, sqlQuery, userLogicOperator);

            sqlQuery.append(" review_count ")
                    .append(reviewCntOperator).append(reviewCntValue).append("n");

            firstCondition = false;
        }
        if (numFriendOpertor != "=, >, <" && isValidNumber(numFriendsValue)) {
            ifFirstCondition(firstCondition, sqlQuery, userLogicOperator);

            sqlQuery.append(" numFriend ")
                    .append(numFriendOpertor).append(numFriendsValue).append("n");

            firstCondition = false;
        }
        if (avgStarsOperator != "=, >, <" && isValidNumber(avgStarValue)) {
            ifFirstCondition(firstCondition, sqlQuery, userLogicOperator);

            sqlQuery.append(" average_stars ")
                    .append(avgStarsOperator).append(avgStarValue).append("n");

            firstCondition = false;
        }
        if (numVotesOperator != "=, >, <" && isValidNumber(numVotesValue )) {
            ifFirstCondition(firstCondition, sqlQuery, userLogicOperator);

            sqlQuery.append(" num_votes ")
                    .append(numVotesOperator).append(numVotesValue);

            firstCondition = false;
        }

        System.out.println(sqlQuery.toString());


        //display the results
        try (Connection connection = getConnection()){

            Statement queryUserStm = connection.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,
                    ResultSet.CONCUR_READ_ONLY);
            ResultSet results = queryUserStm.executeQuery(sqlQuery.toString());

            String [] columns = new String [] {"Joined Date", "Num Votes", "Review Cnt",
                    "User Name", "User Id", "Avg Stars", "Num Friends"};

            displayResults(results, columns, resultTableForUser, extraPanelForResult, "user");

        } catch (SQLException | ClassNotFoundException e) {
            e.printStackTrace();
        }

    }

Review Query

设置好review筛选条件后，点击查询结果中任意的一条business或者user会发出SQL查询
如下图会发出

SELECt *
FROM REVIEW
WHERe user_id = 'uygg55wWaEP0xTR7dHDg-g'
AND ( stars >2
OR num_votes <100
)

Implementation

private StringBuilder getReviewList(String type, String id, String [] columns, StringBuilder sqlQuery) {

        String idType = "";
        String logicOperator = "";
        String dateFrom = dateFromTextField.getText();
        String dateTo = dateToTextField.getText();
        String reviewStars = starsTextField.getText();
        String reviewStarsOperator = starsComboBox.getSelectedItem().toString();
        String reviewVotes = votesTextField.getText();
        String reviewVotesOperator = votesComboBox.getSelectedItem().toString();

        if (type == "business") {
            logicOperator = businessSearchComboBox.getSelectedItem().toString();
            idType  = "business_id";
        }
        else if (type == "user") {
            logicOperator = userSearchComboBox.getSelectedItem().toString();
            idType  = "user_id";
        }

        sqlQuery.append("SELECT *").append("n")
                .append("FROM REVIEW").append("n")
                .append("WHERe ").append(idType).append(" = '").append(id).append("'n");


        boolean firstCondition = true;

        if (isValidDate(dateFrom)) {
            if (firstCondition) {
                sqlQuery.append("AND (");
            }
            else  {
                sqlQuery.append(logicOperator);
            }

            sqlQuery.append(" review_date").append(" >= ")
                    .append(" TO_DATE('").append(dateFrom).append("','").append("YYYY-MM-DD')")
                    .append("n");

            firstCondition =  false;
        }
        if (isValidDate(dateTo)) {
            if (firstCondition) {
                sqlQuery.append("AND (");
            }
            else  {
                sqlQuery.append(logicOperator);
            }

            sqlQuery.append(" review_date").append(" <= ")
                    .append(" TO_DATE('").append(dateTo).append("','").append("YYYY-MM-DD')")
                    .append("n");

            firstCondition =  false;
        }
        if (reviewStarsOperator != "=, >, <" && isValidNumber(reviewStars)) {
            if (firstCondition) {
                sqlQuery.append("AND (");
            }
            else  {
                sqlQuery.append(logicOperator);
            }

            sqlQuery.append(" stars ")
                    .append(reviewStarsOperator).append(reviewStars).append("n");

            firstCondition =  false;
        }
        if (reviewVotesOperator != "=, >, <" && isValidNumber(reviewVotes)) {
            if (firstCondition) {
                sqlQuery.append("AND (");
            }
            else  {
                sqlQuery.append(logicOperator);
            }

            sqlQuery.append(" num_votes ")
                    .append(reviewVotesOperator).append(reviewVotes).append("n");

            firstCondition =  false;
        }

        if (!firstCondition) {
            sqlQuery.append(")");
        }
        System.out.println(sqlQuery.toString());

        return sqlQuery;
    }

Notes

如何写SQL 查询语句会极大的影响查询速度和代码复杂度

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