uniapp-sample-scan/utils/database.js

//打开数据库(创建数据库或者有该数据库就打开)
var name = "sample_storage"  // 数据库名称

// 防止数据中的 单引号 报错
export function html2Escape(str) {
    // console.log("str",str,typeof str)
    if(typeof str === "string"){
        return str.replace(/'/g, "''");
    }else if(typeof str === "object"){
        return JSON.stringify(str).replace(/'/g, "''");
    }else{
        return str
    }

}

export async function openSqlite(){
    //创建数据库或者打开
    //这plus.sqlite只在手机上运行
    return new Promise((resolve,reject) =>{
        if(isOpen()){
            // console.log("数据库已经打开了")
            resolve("数据库已经打开");
            return true
        }
        // console.log("开始打开数据库")
        plus.sqlite.openDatabase({
            name,  //数据库名称
            path:`_doc/${name}.db`,   //数据库地址，uniapp推荐以下划线为开头，这到底存在哪里去了，我也不清楚，哈哈
            success(){
                // console.log("成功打开数据库")
                resolve(); //成功回调
            },
            fail(e){
                // console.log("失败打开数据库",e)
                reject(e); //失败回调
            }
        })
    })
}
//判断数据库是否打开
export function isOpen(){
    //数据库打开了就返回true,否则返回false
    var open = plus.sqlite.isOpenDatabase({
        name,
        path: `_doc/${name}.db`
    })
    return open;
}
//关闭数据库
export function closedb(){
    return new Promise((resolve,reject) =>{
        plus.sqlite.closeDatabase({
            name,
            success(e){
                resolve(e);
            },
            fail(e){
                reject(e);
            }
        })
    })
}
// 执行sql语句
export function executeSql(sql){
    return new Promise((resolve,reject) =>{
        //创建表格在executeSql方法里写
        // console.log("开始执行自定义sql",sql)
        plus.sqlite.executeSql({
            name,
            //表格创建或者打开，后面为表格结构
            sql:sql,
            success(e){
                resolve(e);
            },
            fail(e){
                console.error("自定义sql报错",e)
                reject(e);
            }
        })
    })
}
// 查询所有数据表名
export async function getTable(){
    return selectSql("select * FROM sqlite_master where type='table'")
}
// 获取表的所有字段
export async function getAllField(tableName){
    return selectSql(`PRAGMA table_info([${tableName}])`)
}

// 查询表数据总条数
export const getCount = (tableName,whereObj={}) => {
    let sql = `select count(*) as num from ${tableName} where 1 `
    if(Object.keys(whereObj).length>0){
        for(let i in whereObj){
            sql += ` and ${i} = '${whereObj[i]}' `
        }
    }
    console.log("getCount的SQL",sql)
    return selectSql(sql)
}
// 查询表是否存在
export const isTable = (tableName) => {
    return new Promise((resolve, reject) => {
        plus.sqlite.selectSql({
            name: name,
            sql: `select count(*) as isTable FROM sqlite_master where type='table' and name='${tableName}'`,
            success(e) {
                resolve(e[0].isTable ? true : false);
            },
            fail(e) {
                console.log(e)
                reject(e);
            }
        })
    })
}

// 添加数据
export async function addSql(tableName,obj={}) {

    if (Object.keys(obj).length>0) {
        // 获取数据库的字段
        let fieldList = await getAllField(tableName)
        // 取数据库有的字段
        let keys = intersection(fieldList,obj)
        let keyStr = keys.toString()
        let valStr = ''
        keys.forEach((item, index) => {
            valStr += (`'${html2Escape(obj[item])}',`)
        })
        valStr = valStr.substring(0,valStr.length-1)
        let sqlStr = `insert into ${tableName}(${keyStr}) values(${valStr})`
        console.log("addSql",sqlStr)
        return executeSql(sqlStr)
    } else {
        return new Promise((resolve, reject) => {
            reject("错误")
        })
    }
}


// 修改数据
export async function updateSql(tableName, setData, whereObj={}){
    if(!Object.keys(whereObj).length){
        return new Promise((resolve, reject) => {
            reject("请传whereObj")
        });
        return false
    }
    if (setData&&JSON.stringify(setData) !== '{}') {
        // 获取数据库的字段
        let fieldList = await getAllField(tableName)
        let dataKeys = intersection(fieldList,setData)
        let setStr = ''
        // console.log("dataKeys",tableName,dataKeys)
        dataKeys.forEach((item, index) => {
            // console.log(setData[item])
            setStr += (
                `${item} = '${setData[item]}',`)
        })
        setStr = setStr.substring(0,setStr.length-1)
        let sql = `update ${tableName} set ${setStr} where 1 `
        for(let i in whereObj){
            sql += ` and ${i} = '${whereObj[i]}' `
        }
        // console.log("修改数据的sql",sql)
        return executeSql(sql)
    } else {
        return new Promise((resolve, reject) => {
            reject("错误")
        });
    }
}

//删除数据库数据
export async function deleteSql(tableName,whereObj={}){
    if (tableName&&JSON.stringify(whereObj) !== '{}') {
        let dataKeys = Object.keys(whereObj)
        let setStr = ''
        dataKeys.forEach((item, index) => {
            console.log(whereObj[item])
            setStr += (
                `${item}='${whereObj[item]}' ${dataKeys.length - 1 !== index ? " and " : ""}`)
        })
        console.log("删除sql",`-- delete from ${tableName} where ${setStr}`)
        let sql = `delete from ${tableName} where ${setStr}`
        return executeSql(sql)
    } else {
        return new Promise((resolve, reject) => {
            reject("错误")
        });
    }
}

/**
 * 获取分页数据库数据
 * @param tableName 表名称
 * @param pageObj  分页数据，如  {current:1,size:10}
 * @param whereObj 查询
 * @param orderBy 排序
 * @returns {Promise<unknown>}
 */
export const getPageList = async (tableName,pageObj,whereObj={},orderBy) => {
    // console.log("数据库",tableName,pageObj,whereObj,orderBy)
    let current = parseInt(pageObj.current)
    let size = parseInt(pageObj.size)
    // console.log("数据库11")
    let pages = 0,total = 0 // pages为总页数，total为总数据条数
    let sql = ''
    let numindex = 0
    await getCount(tableName,whereObj).then((resNum) => {
        console.log("resNum",resNum,size)
        pages = Math.ceil(resNum[0].num / size)
        total = resNum[0].num
    })
    if(((current - 1) * size) == 0) {
        numindex = 0
    } else {
        numindex = ((current - 1) * size) + 1
    }
    sql = `select * from ${tableName} where 1 `
    if(Object.keys(whereObj).length>0){
        for(let i in whereObj){
            sql += ` and ${i} = '${whereObj[i]}' `
        }
    }
    if(orderBy) {
        sql += ` order by ${orderBy} `
    }
    sql += ` limit ${numindex},${size}`
    console.log("分页sql，",sql)
    if (pages < current - 1) {
        return new Promise((resolve, reject) => {
            reject("无数据")
        });
    } else {
        return new Promise((resolve, reject) => {
            plus.sqlite.selectSql({
                name: name,
                sql:sql ,
                success(e) {
                    resolve({
                        code:0,
                        data:{
                            data:{
                                records:e,
                                pages,
                                total
                            }
                        },
                        msg:null
                    });
                },
                fail(e) {
                    reject({data:e,code:500,msg:e});
                }
            })
        })
    }
}
/**
 * 自定义语句查询，数据库数据
 * @param sql sql语句
 * @returns {Promise<any>}
 */
export const selectSql = (sql) => {
    // console.log("查询的sql",sql)
    return new Promise((resolve, reject) => {
        plus.sqlite.selectSql({
            name: name,
            sql: sql,
            success(e) {
                resolve(e);
            },
            fail(e) {
                console.log("查询报错",e)
                reject(e);
            }
        })
    })
}

/**
 * 查询数据库数据
 * @param tableName 表名
 * @param searchObj 查询的对象
 * @param orderBy 排序, 如 "id desc"
 * @param selectStr
 * @returns {Promise<any>}
 */
export const selectList = (tableName,searchObj={},orderBy="") => {
    let setStr = ''
    let sql = ''
    if (tableName) {
        if (JSON.stringify(searchObj) !== '{}') {
            let dataKeys = Object.keys(searchObj)
            dataKeys.forEach((item, index) => {
                // console.log(searchObj[item])
                setStr += (
                    `${item}='${html2Escape(searchObj[item])}' ${dataKeys.length - 1 !== index ? " and " : ""}`)
            })
        }
        sql = `select * from ${tableName} `
        sql += setStr ? ` where ${setStr} ` : ""

        if(orderBy) {
            sql += ` order by ${orderBy} `
        }
        console.log("查询数据库数据",sql)
        return selectSql(sql)
    } else {
        return new Promise((resolve, reject) => {
            reject("错误")
        });
    }
}


//将SQL语句进行拼接values(),()...然后再一次性插入，
export async function insertAll(tableName="",data=[]){
    let sql = ""
    // 获取数据库的字段
    try{
        let fieldList = await getAllField(tableName)
        // console.log("fieldList",fieldList)
        if (tableName && data.length > 0) {
            // 取交集的字段，才是合法的，能存进数据库的字段（注意：取的字段，是按照第一条数据的字段，进行赋值的）
            let keys = intersection(fieldList,data[0])
            let keyStr = keys.toString()
            console.log("keyStr",keyStr)

            sql = `insert into ${tableName} (${keyStr}) values`;
            for (let i = 0; i < data.length; i++) {
                sql += "(";
                for (const [k, v] of keys.entries()) {
                    // console.log("data[i][v]",k,v,data[i][v],data)
                    sql += `'${html2Escape(data[i][v])}',`
                }
                sql = sql.substring(0, sql.length - 1)
                sql += "),";
            }
            sql = sql.substring(0, sql.length - 1)
            console.log("批量插入的sql", sql)
        } else {
            this.$msg("表名为空或者插入数据为空")
        }
    }catch(e){
        console.error("批量插入报错",e)
    }
    return executeSql(sql)
}

/**
 * 批量修改 data数组 field关键字段 批量修改函数 传参方式
 * @param tableName 表名
 * @param data 需要修改的数据
 * @param field 表主键字段，通常是 id
 * @returns {Promise<unknown>}
 */
export async function batchUpdate(tableName='',data=[],field=''){

    let sql = ""
    let con = [];
    let con_sql = [];
    let fields = [];
    let value
    let temp
    try{

        if (!tableName || !data || !field) {
            return false;
        } else {
            sql = 'UPDATE ' + tableName;
        }

        for (let key in data) {
            value = data[key]
            let x = 0;
            let v
            // console.log("value",value)
            for (let k in value) {
                v = value[k]
                if (k != field && !con[x] && x == 0) {
                    con[x] = ` set ${k} = (CASE ${field} `;
                } else if (k != field && !con[x] && x > 0) {
                    con[x] = ` ${k} = (CASE ${field} `;
                }
                if (k != field) {
                    temp = value[field];
                    con_sql[x] = con_sql[x] ? con_sql[x] : ""
                    con_sql[x] += ` WHEN '${temp}' THEN '${html2Escape(v)}' `;
                    x++;
                }
            }
            temp = value[field];
            // console.log("temp",fields,temp)
            if (fields.indexOf(temp)===-1) {
                fields.push(temp)
            }
        }
        let num = con.length - 1;
        for (let [key, value] of con.entries()) {
            for (let [k, v] of con_sql.entries()) {
                if (k == key && key < num) {
                    sql += value + v + ' end),';
                } else if (k == key && key == num) {
                    sql += value + v + ' end)';
                }
            }
        }
        let str = fields.join(",");
        sql += ` where ${field} in(${str})`;
        console.log("批量更新的sql", sql)


    }catch(e){
        console.error("批量修改报错",e)
    }
    return executeSql(sql)
}



//////////////////////////////////////////////////////////////////////






// 合并数据
export const mergeSql = (name,tableName,tabs) => {
    if (!tabs || tabs.length == 0) {
        return new Promise((resolve, reject) => {
            reject("错误")
        })
    }
    let itemValStr = ''
    tabs.forEach((item, index) => {
        let itemKey = Object.keys(item)
        let itemVal = ''
        itemKey.forEach((key, i) => {
            if (itemKey.length - 1 == i) {
                if (typeof item[key] == 'object') {
                    itemVal += (`'${JSON.stringify(item[key])}'`)
                } else {
                    itemVal += (`'${item[key]}'`)
                }
            } else {
                if (typeof item[key] == 'object') {
                    itemVal += (`'${JSON.stringify(item[key])}',`)
                } else {
                    itemVal += (`'${item[key]}',`)
                }
            }
        })
        if (tabs.length - 1 == index) {
            itemValStr += ('(' + itemVal + ')')
        } else {
            itemValStr += ('(' + itemVal + '),')
        }
    })
    let keys = Object.keys(tabs[0])
    let keyStr = keys.toString()
    let sql = `insert or ignore into ${tableName} (${keyStr}) values ${itemValStr}`
    return executeSql(sql)
}
/**
 * 过滤非数据表的字段，使其不报错
 * @param fieldList ，使用 getAllField()函数查询出来的数据
 * @param obj 数据
 * @returns []
 */
export function intersection(fieldList=[],obj){
    // 获取数据库的字段
    let arrField = {}
    for(let i in fieldList){
        arrField[fieldList[i].name] = null
    }
    // 取交集的字段，才是合法的，能存进数据库的字段
    let keys = []
    for (let i in arrField) {
        if (obj.hasOwnProperty(i)) {
            keys.push(i)
        }
    }

    return keys
}