大家好哇,我是梦辛工作室的灵,在最近的开发过程中又遇到了一些问题,这次是关于本地存储的,在小程序面进行存储一些数据,本来就依靠小程序的本地储存API 就可以实现,但数据量小还好,如果数据量大那么就不在方便了,主要就没办法查询或批量修改,我这次主要是因为小程序有无网络状态下也需要可以正常运行,所以我想着能不能直接把数据库放在本地算了,就样子就算没有网络也可以正常运行,然后有网络的时候再去做同步就可以,本着这样的想法,我就瞄上了小程序的文件储存API,如果我把我所需要的数据存在JSON里面然后再存在本地文件夹就可以了,然后就按照自己的想法写出来了MxLocalBase,目前已简单实现的数据库的建立、数据表的建立、事务、索引等,由于JS是单线程运行的,所以也就不用担心多线程的问题,下面来看下整体结构:
核心类就是bin下面的3个文件,util 文件夹里面主要是 用来做文件储存的辅助类,
先简单说明下如何使用吧
这3个类可以自己独立运行,Connect 可以用于管理 DataBase ,DataBase可以用于管理多个Table类
Table类用于管理文件数据
先说Connect的使用方法:
let curConn = new Connect(wx.getFileSystemManager(), basePath + path);
let databaseList = curConn.showDataBases(); //获取数据库列表
curConn.useDataBase(baseName); //选择目前操作的数据库
let tableList = curConn.showTableList(); //获取当前数据库的数据表列表
let curDataBase = curConn.getCurDataBase();//获取当前操作的数据库对象 即使 DataBase 类
curConn.createTable(tableName,options) //创建数据表
//options 为数据表结构,其格式为:[item ,....]
//item :{"name":"列名称":, "type":"列类型 目前支持 string, number,object,boolean" ,
// "default":"默认值", "increment":"是否自动增加", "notNull":"是否不为null",
//"primaryKey":"是否为主键", "uni":"是否为唯一键", "comment":"说明"}
curConn.doAddTableSet(tableName,itemSet);// 数据表添加列 itemSet 和上述 item 一个格式
curConn.deleteDataBase(databaseName); //删除数据库
curConn.createDataBase(databaseName,error); //创建数据库
let table = tryConnectTable(tableName); //获取当前数据表对象 即 Table 类
curConn.deleteTable(tableName); // 删除数据表
DataBase 的使用方法:
let curDataBase = curConn.getCurDataBase(); //可以这样获取DataBase对象,也可以直接创建
let curDataBase = new DataBase(wx.getFileSystemManager(),databaseName,BasePath);
curDataBase.createTable(tableName,options); // 创建数据表 同上
let curTable = curDataBase.tryConnectTable(tableName); //获取数据表 也同上
DataBase 创建的时候会读取本地的文件夹列表,视为数据表,并创建其数据表对象
Table的使用方法:
let curTable = curDataBase.tryConnectTable(tableName); //获取数据表 也可以直接创建
let curtable = new Table(wx.getFileSystemManager(), tableName, BasePath);
curtable.setAutoCommit(false); // 开启事务
curtable.addTableSet(itemSet); // 添加列,属性同 上item
curtable.modiftyTableSet(name,itemSet); // 修改列,name 列名称 itemSet属性同 上item
curtable.deleteTableSet(name); //删除列 name 为列名称
curtable.modifyData(updateData, whereData); //修改数据 updateData 格式为 [{name:"列名",value:"值"}]
// whereData 的格式为: [{name:"列名",type:"比对类型",value:"值"}]
//目前比对在 util里面的 compareMap,并有其对应的判断方法
curtable.modifyDataByPathIndex(updateData, pathIndex, dataIndex)
//修改数据 updateData 格式为 [{name:"列名",value:"值"}]
//pathIndex 为数据所保存的文件索引,文件目前会按1000条数据划分文件,如 data_0.json pathIndex 就为0
//dataIndex 为数据所在文件的json中的行数,每个数据返回是都会有 pathIndex, dataIndex
curtable.deleteDataByPathIndex({pathIndex, dataIndex}) //删除指定数据
curtable.deleteData(whereData) //删除数据,同上
curtable.selectData(whereData, mapFun, limitData, orderByData) //查询数据 whereData 格式同上 mapFun为自定义方法
//,每查询到合适的数据就会主动调用该方法
//limitData 为 {start:开始行数,count:返回条数}
//orderByData 为排序对象 格式为:[{name:'列名',type:'排序规则,desc 或 asc'},....]
curtable.addData(itemData);//添加的数据,格式为当前数据表结构
curtable.commit();//提交数据,若不开始事务,修改数据后,500ms 后就会自动保存到文件里
好了,然后在和大家讲下原理把,其实核心还是Table 类,其他的都只是用于管理罢了,
Table 类里面的核心结构为
//数据列表
dataJsonList:[
{
path: 'data_0.json', // 文件名称
pathIndex: index, //文件索引
data: [], //具体数据
read: 0, //读了几次,用于清理内存时,按读取次数清理,越小越容易被清理
modify: 0, //修改位,用于保存时判断是否需要重新写入文件
primaryKeyIndex:{}, //主键索引映射
uniIndex:{}, //唯一键索引映射
indexMap:{} //其他索引映射
}
]
//数据表结构
setJson:[
{
"data": [{
"name": "username",
"default": "",
"type": "string",
"uni": true
}, {
"name": "password",
"default": "",
"type": "string",
"uni": false
}, {
"name": "showname",
"type": "string",
"default": "",
"uni": false
}],
"index": {
"username": 0,
"password": 1,
"showname": 2
}
}
]
目前我这边还写了一个微信小程序的展示界面:
代码已上传至github ,有兴趣的同学可以去看下,有什么问题还请大佬们多多指教
github传送门
gitee传送门
还是依旧老规矩,上源码:
Connect.js
import FileManager from "../util/FileManager";
import DataBase from "./DataBase";
class Connect {
constructor(manager,BasePath){
this.fileManmger = new FileManager(manager);
this.BasePath = BasePath;
try{
this.fileManmger.accessSync(BasePath);
} catch (e){
this.fileManmger.mkdirSync({dirPath:BasePath,recursive:true});
}
this.connect = 1;
}
checkFileExsites(filePath){
try{
this.fileManmger.accessSync(filePath);
} catch (e){
return false;
}
return true;
}
isConnect(){
return this.connect == 1;
}
isSelectDataBase(){
if(this.databaseName){
if(!this.database || this.database.databaseName != this.databaseName){
this.database = new DataBase(this.fileManmger,this.databaseName,this.BasePath);
}
}
return typeof this.databaseName == "string";
}
useDataBase(databaseName,create){
if(!this.isConnect()){
throw("当前数据库未连接");
}
let databasePath = this.BasePath + "/" + databaseName;
if(!this.checkFileExsites(databasePath)){
if(create){
this.fileManmger.mkdirSync({dirPath:databasePath, recursive:true});
} else {
throw("数据库:" + databaseName + " 不存在");
}
}
this.databaseName = databaseName;
}
createDataBase(databaseName,error){
if(!this.isConnect()){
throw("当前数据库未连接");
}
let databasePath = this.BasePath + "/" + databaseName;
if(!this.checkFileExsites(databasePath)){
this.fileManmger.mkdirSync({dirPath:databasePath, recursive:true});
this.databaseName = databaseName;
} else {
if(error)throw("数据库:" + databaseName + " 已存在,请勿重复创建");
}
}
deleteDataBase(databaseName){
if(!this.isConnect()){
throw("当前数据库未连接");
}
let databasePath = this.BasePath + "/" + databaseName;
if(!this.checkFileExsites(databasePath)){
throw("数据库:" + databaseName + " 不存在");
}
this.fileManmger.rmdirSync({dirPath:databasePath,recursive:true});
if(this.databaseName == databaseName){
this.databaseName = "";
this.database = "";
}
}
tryConnectTable(tableName){
if(!this.isConnect()){
throw("当前数据库未连接");
}
if(!this.isSelectDataBase()){
throw("当前未选择数据库");
}
return this.database.tryConnectTable(tableName);
}
showDataBases(){
if(!this.isConnect()){
throw("当前数据库未连接");
}
return this.fileManmger.readdirSync({dirPath:this.BasePath});
}
showTableList(){
if(!this.isConnect()){
throw("当前数据库未连接");
}
if(!this.isSelectDataBase()){
throw("当前未选择数据库");
}
return this.database.showTables();
}
doAddTableSet(tableName,itemSet){
if(!this.isConnect()){
throw("当前数据库未连接");
}
if(!this.isSelectDataBase()){
throw("当前未选择数据库");
}
return this.database.doAddTableSet(tableName,itemSet);
}
getCurDataBase(){
if(!this.isConnect()){
throw("当前数据库未连接");
}
if(!this.isSelectDataBase()){
throw("当前未选择数据库");
}
return this.database;
}
createTable(tableName,options){
if(!this.isConnect()){
throw("当前数据库未连接");
}
if(!this.isSelectDataBase()){
throw("当前未选择数据库");
}
this.database.createTable(tableName,options);
}
deleteTable(tableName){
if(!this.isConnect()){
throw("当前数据库未连接");
}
if(!this.isSelectDataBase()){
throw("当前未选择数据库");
}
this.database.deleteTable(tableName);
}
doShowTableSet(tableName){
if(!this.isConnect()){
throw("当前数据库未连接");
}
if(!this.isSelectDataBase()){
throw("当前未选择数据库");
}
return this.database.doShowTableSet(tableName);
}
closeConnect(){
this.connect = 0;
}
}
export default Connect;
DataBase.js
import { log } from "../util/util";
import Table from "./Table";
class DataBase {
tableMap = {}
tableList = []
constructor(manager,databaseName,BasePath){
this.fileManmgerObject = manager;
this.databaseName = databaseName;
this.BasePath = BasePath;
this.loadTableList();
}
get CurPath(){
return this.BasePath + "/" + this.databaseName;
}
get CurTablePath(){
return this.BasePath + "/" + this.databaseName + "/" + this.tableName;
}
createTable(tableName,options){
let tablePath = this.CurPath + "/" + tableName;
if(this.tableMap[tableName]){
throw("已存在数据表:" + tableName + " 请勿重复创建")
}
try{
this.fileManmger.mkdirSync({dirPath:tablePath, recursive:true});
this.fileManmger.mkdirSync({dirPath:tablePath + "/set", recursive:true});
this.fileManmger.mkdirSync({dirPath:tablePath + "/data", recursive:true});
this.fileManmger.mkdirSync({dirPath:tablePath + "/index", recursive:true});
if(options){
this.setTableOptions(tableName,options);
}
this.tableMap[tableName] = new Table(this.fileManmger,tableName,this.CurPath);
} catch (e){
console.log(e)
}
}
loadTableList(){
let tableList = [];
try{
tableList = this.fileManmger.readdirSync({dirPath:this.CurPath});
} catch(e) {
log(e);
}
for(let tableName of tableList){
this.tableMap[tableName] = new Table(this.fileManmger,tableName,this.CurPath);
}
this.tableList = tableList;
}
setTableOptions(tableName,options){
this.tryConnectTable(tableName);
this.tableMap[tableName].setTableOptions(options);
}
tryConnectTable(tableName){
if(!this.tableMap[tableName]){
throw("不存在数据表:" + tableName)
}
if(!this.tableMap[tableName].isConnect){
this.tableMap[tableName] = new Table(this.fileManmger,tableName,this.CurPath);
}
return this.tableMap[tableName];
}
get fileManmger(){
return this.fileManmgerObject;
}
doAddTableSet(tableName,itemSet){
this.tryConnectTable(tableName);
return this.tableMap[tableName].addTableSet(itemSet);
}
showTables(){
return this.tableList;
}
deleteTable(tableName){
let tablePath = this.CurPath + "/" + tableName;
if(!this.tableMap[tableName]){
throw("数据表:" + tableName + " 不存在");
}
this.fileManmger.rmdirSync({dirPath:tablePath,recursive:true});
this.tableMap[tableName] = {};
delete this.tableMap[tableName];
this.tableList.splice(this.tableList.indexOf(tableName),1);
}
doShowTableSet(tableName){
this.tryConnectTable(tableName);
return this.tableMap[tableName].setJson.data;
}
}
export default DataBase;
Table.js文章来源:https://www.toymoban.com/news/detail-476932.html
import FileManager from "../util/FileManager";
import util from "../util/util"
let typeMap = {
"string": 1,
"number": 1,
"boolean": 1,
"object": 1
}
let saveSetTimeout = 0;
let saveDataJsonTimeout = 0;
let releaseDataJsonTimeout = 0;
let saveIndexJsonTimeout = 0;
let MaxSaveLines = 1000; //一个文件最大保存1000条数据
let releaseLimitTime = 30 * 1000; // 读取数据 或 保存数据后多少秒清理内存
let releaseSaveCount = 3; // 释放内存数据时 保存数量 按readCount排序来释放
let saveLimitTime = 500;// 每隔500ms 才保存一次
class Table {
constructor(manager, tableName, BasePath) {
if (manager instanceof FileManager) {
this.fileManmgerObject = manager;
} else {
this.fileManmgerObject = new FileManager(manager);
}
this.tableName = tableName;
this.BasePath = BasePath;
this.autoCommit = true;
this.connect();
}
setAutoCommit(autoCommit) {
this.autoCommit = autoCommit;
}
connect() {
if (this.isConnect) {
return true;
}
try {
this.fileManmger.accessSync(this.CurPath);
} catch (e) {
throw ("当前数据表不存在");
}
this.isConnect = 1;
this.loadTableSet();
this.loadTableDataPath();
this.loadTableIndex();
return true;
}
close() {
this.checkConnect();
if (this.autoCommit) {
this.commit();
} else {
this.rollback();
}
this.connect = 1;
}
get fileManmger() {
return this.fileManmgerObject;
}
get CurPath() {
return this.BasePath + "/" + this.tableName;
}
loadTableSet() {
this.checkConnect();
this.setJson = this.readFileSync("/set/set.json", {
data: [],
index: {}
})
}
setTableOptions(options) {
this.checkConnect();
if (this.setJson.data.length > 0) {
throw ("当前数据表已存在结构,请勿重复设置");
}
let setJson = {
data: [],
index: {}
};
if (!options.column || typeof options.column[0] != "object") {
throw ("错误的列表设置");
}
let hasPrimaryKey = false;
for (let item of options.column) {
if (!item.name) {
throw ("列表必须含有name字段");
}
if (item.autoIncrement && item.type != "number") {
throw ("自动增加类型只能为数字");
}
if (item.primaryKey) {
if (hasPrimaryKey) {
throw ("主键仅能有一个字段");
}
hasPrimaryKey = true;
}
setJson.data.push({
name: item.name,
defaultValue: item.defaultValue || undefined,
autoIncrement: item.autoIncrement || false,
comment: item.comment || "无",
type: item.type || "any",
notNull: item.notNull,
primaryKey: item.primaryKey || false,
uni: item.uni
})
setJson.index[item.name] = setJson.data.length - 1;
}
this.setJson = setJson;
this.saveSetJson();
}
readFileSync(path, defaultValue) {
let result = defaultValue;
try {
let dataPath = this.CurPath + path;
this.fileManmger.accessSync(dataPath);
let readData = this.fileManmger.readFileSync({
filePath: dataPath,
encoding: "utf-8",
})
result = JSON.parse(readData)
} catch (e) {
util.log(e);
}
return result;
}
loadTableDataPath() {
this.checkConnect();
try {
let dataJsonPath = this.CurPath + "/data";
let resultData = this.fileManmger.readdirSync({ dirPath: dataJsonPath });
if (!(resultData instanceof Array)) {
resultData = [];
}
let result = [];
for (let index = 0; index < resultData.length; index++) {
result.push({
path: 'data_' + index + '.json',
pathIndex: index,
data: [],
read: 0,
modify: 0,
})
}
this.dataJsonList = result;
} catch (e) {
util.log(e);
this.dataJsonList = [];
}
}
/**
*
* @param {
* name:"字段名称",
* type:"字段类型",
* primaryKey:"是否为主键",
* default:"默认值",
* uni:"是否为唯一键"
* } itemSet 字段属性
*/
addTableSet(itemSet) {
this.checkConnect();
this.checkItemSet(itemSet);
let setJson = this.setJson;
if (typeof setJson.index[itemSet.name] == "number") {
throw ("当前字段已存在,请勿重复创建");
}
if (itemSet.uni && typeof itemSet.default != "undefined") {
throw ("唯一键默认值仅能为undefined");
}
for (let item of setJson.data) {
if (itemSet.primaryKey && item.primaryKey) {
throw ("已存在主键");
}
}
let dataJsonList = this.dataJsonList;
for (let dataJson of dataJsonList) {
this.loadDataJson(dataJson);
let index = 0;
for (let item of dataJson.data) {
if (typeof itemSet.default == "undefined") {
item[itemSet.name] = undefined;
} else {
item[itemSet.name] = itemSet.default;
if (dataJson.indexMap[itemSet.name]) {
if (!dataJson.indexMap[itemSet.name][itemSet.default]) {
dataJson.indexMap[itemSet.name][itemSet.default] = [index];
} else {
dataJson.indexMap[itemSet.name][itemSet.default].push(index);
}
}
}
index++;
}
dataJson.modify = 1;
}
setJson.data.push(itemSet);
setJson.index[itemSet.name] = setJson.data.length - 1;
this.saveSetJson(setJson);
this.commit();
}
modiftyTableSet(name, itemSet) {
this.checkConnect();
this.checkItemSet(itemSet);
let setJson = this.setJson;
if (typeof setJson.index[name] != "number") {
throw ("修改字段不存在");
}
if (typeof setJson.index[itemSet.name] != "number") {
throw ("目标字段已存在,请勿重复创建");
}
if (itemSet.uni && typeof itemSet.default != "undefined") {
throw ("唯一键默认值仅能为undefined");
}
if (itemSet.primaryKey && typeof setJson.index.primaryKey) {
throw ("当前表已存在主键");
}
let isIndex = false;
if (this.indexJsonMap[srcSetJson.name]) {
isIndex = true;
}
let dataJsonList = this.dataJsonList;
for (let dataJson of dataJsonList) {
this.loadDataJson(dataJson);
let indexMap = {};
let index = 0;
for (let item of dataJson.data) {
let tempValue = item[name];
if (typeof tempValue == "undefined") {
item[itemSet.name] = itemSet.default;
} else {
item[itemSet.name] = tempValue;
indexMap[tempValue] = index;
if (dataJson.indexMap[itemSet.name]) {
if (!dataJson.indexMap[itemSet.name][tempValue]) {
dataJson.indexMap[itemSet.name][tempValue] = [index];
} else {
dataJson.indexMap[itemSet.name][tempValue].push(index);
}
}
}
if (isIndex) {
delete dataJson.indexMap[itemSet.name];
}
delete item[name];
index++;
}
if (itemSet.primaryKey) {
dataJson.primaryKey = indexMap;
} else if (itemSet.uni) {
dataJson.uniIndex[itemSet.name] = indexMap;
delete dataJson.uniIndex[name];
}
if (srcSetJson.uni) {
delete dataJson.uniIndex[name];
} else if (srcSetJson.primaryKey) {
dataJson.primaryKey = {};
}
dataJson.modify = 1;
}
setJson.data.splice(setJson.index[name], 1);
setJson.data.push(itemSet);
this.reIndexSetJson(setJson);
this.saveSetJson(setJson);
this.commit();
}
deleteTableSet(name) {
this.checkConnect();
let setJson = this.setJson;
if (typeof setJson.index[name] != "number") {
throw ("删除字段不存在");
}
let srcSetJson = setJson.data[setJson.index[name]];
let dataJsonList = this.dataJsonList;
let isIndex = false;
if (this.indexJsonMap[srcSetJson.name]) {
isIndex = true;
}
for (let dataJson of dataJsonList) {
this.loadDataJson(dataJson);
for (let item of dataJson.data) {
delete item[name];
}
if (srcSetJson.uni) {
delete dataJson.uniIndex[name];
}
if (srcSetJson.primaryKey) {
dataJson.primaryKeyIndex = {};
}
if (isIndex) {
delete dataJson.indexMap[itemSet.name];
}
dataJson.modify = 1;
}
setJson.data.splice(setJson.index[name], 1);
this.reIndexSetJson(setJson);
this.saveSetJson(setJson);
this.commit();
}
checkConnect() {
if (!this.isConnect) {
throw ("未连接当前数据表")
}
}
checkItemSet(itemSet) {
if (!itemSet.name) {
throw ("列表必须含有name字段");
}
if (!itemSet.type) {
throw ("列表必须设置type字段");
}
if (!typeMap[itemSet.type]) {
throw ("type只能为:string、number、boolean、object");
}
if (itemSet.autoIncrement && itemSet.type != "number") {
throw ("自动增加类型只能为数字");
}
}
saveSetJson() {
if (saveSetTimeout) {
clearTimeout(saveSetTimeout);
}
saveSetTimeout = setTimeout(() => {
this.fileManmger.writeFileSync({
filePath: this.CurPath + "/set/set.json",
data: JSON.stringify(this.setJson),
encoding: "utf-8"
})
util.log("保存setJson")
util.log(this.setJson)
}, saveLimitTime)
}
saveDataJson(dataJson) {
this.fileManmger.writeFileSync({
filePath: this.CurPath + "/data/" + dataJson.path,
data: JSON.stringify(dataJson),
encoding: "utf-8"
})
util.log("保存dataJson")
util.log(dataJson)
}
doSaveDataJson() {
if (saveDataJsonTimeout) {
clearTimeout(saveDataJsonTimeout);
}
saveDataJsonTimeout = setTimeout(() => {
let dataJsonList = this.dataJsonList;
for (let dataJson of dataJsonList) {
if (dataJson.modify && dataJson.read) {
this.saveDataJson({
data: dataJson.data,
path: dataJson.path,
primaryKeyIndex: dataJson.primaryKeyIndex,
uniIndex: dataJson.uniIndex,
indexMap: dataJson.indexMap || {}
});
dataJson.modify = 0;
}
}
this.releaseDataJson();
}, saveLimitTime)
}
/**
* 读取数据文件
* @param {*} path
*/
readDataJson(path) {
let result = this.readFileSync('/data/' + path, {
data: [],
primaryKeyIndex: {},
uniIndex: {},
indexMap: {}
});
this.releaseDataJson();
return result;
}
/**
* 重置表结构索引
* @param {*} setJson
*/
reIndexSetJson(setJson) {
let indexMap = {};
let index = 0;
for (let item of setJson.data) {
indexMap[item.name] = index;
index++;
}
setJson.index = indexMap;
}
/**
* 修改数据
* @param {*} updateData {name:"列名",value:"值"}
* @param {*} whereData {name:"列名",type:"比对类型",value:"值"}
*/
modifyData(updateData, whereData) {
if (!updateData || !(updateData instanceof Array)) {
throw ("更新数据格式不正确");
}
let primaryKeyValue = undefined;
let uniList = [];
for (let updateJson of updateData) {
let itemIndex = this.setJson.index[updateJson.name];
if (typeof itemIndex != "number") {
throw ("未知列 " + updateJson.name);
}
let item = this.setJson.data[itemIndex];
if (item.primaryKey) {
if (!updateJson.value) {
throw ("主键 " + item.name + " 不能为空")
} else {
primaryKeyValue = updateJson.value;
}
}
if (item.uni) {
if (typeof updateJson.value == "undefined") {
throw ("唯一键 " + item.name + " 不能为空")
} else {
uniList.push({
name: item.name,
value: updateJson.value
});
}
}
if (updateJson.value && typeof updateJson.value != item.type) {
throw ("字段 " + item.name + " 类型不匹配 " + item.type)
}
}
this.checkSaveValue(primaryKeyValue, uniList);
let modifyCount = 0;
this.selectData(whereData, (dataJson, curIndex, targetValue) => {
for (let updateJson of updateData) {
let itemIndex = this.setJson.index[updateJson.name];
let setItem = this.setJson.data[itemIndex];
if (setItem.primaryKey) {
delete dataJson.primaryKeyIndex[targetValue[setItem.name]];
dataJson.primaryKeyIndex[updateJson.value] = curIndex;
} else if (setItem.uni) {
delete dataJson.uniIndex[setItem.name][targetValue[setItem.name]];
dataJson.uniIndex[setItem.name][updateJson.value] = curIndex;
}
if (this.indexJsonMap[setItem.name]) {
delete dataJson.indexMap[setItem.name][targetValue[setItem.name]];
if (dataJson.indexMap[setItem.name][updateJson.value] instanceof Array) {
dataJson.indexMap[setItem.name][updateJson.value].push(curIndex);
} else {
dataJson.indexMap[setItem.name][updateJson.value] = [curIndex];
}
}
targetValue[updateJson.name] = updateJson.value;
}
dataJson.modify = 1;
modifyCount++;
})
if (modifyCount > 0) {
if (this.autoCommit) {
this.commit();
}
}
return modifyCount;
}
/**
* 修改数据
* @param {*} updateData {name:"列名",value:"值"}
*/
modifyDataByPathIndex(updateData, pathIndex, dataIndex) {
if (!updateData || !(updateData instanceof Array)) {
throw ("更新数据格式不正确");
}
console.log(updateData);
let primaryKeyValue = undefined;
let uniList = [];
for (let updateJson of updateData) {
let itemIndex = this.setJson.index[updateJson.name];
if (typeof itemIndex != "number") {
throw ("未知列 " + updateJson.name);
}
let item = this.setJson.data[itemIndex];
if (item.primaryKey) {
if (!updateJson.value) {
throw ("主键 " + item.name + " 不能为空")
} else {
primaryKeyValue = updateJson.value;
}
} else if (item.uni) {
if (typeof updateJson.value == "undefined") {
throw ("唯一键 " + item.name + " 不能为空")
} else {
uniList.push({
name: item.name,
value: updateJson.value
});
}
}
if (updateJson.value && typeof updateJson.value != item.type) {
throw ("字段 " + item.name + " 类型不匹配 " + item.type)
}
}
this.checkSaveValue(primaryKeyValue, uniList);
let modifyCount = 0;
let dataJson = this.dataJsonList[pathIndex];
let curIndex = dataIndex;
this.loadDataJson(dataJson);
let targetValue = dataJson.data[dataIndex];
if (!targetValue || targetValue.__delete) {
return modifyCount;
}
for (let updateJson of updateData) {
let itemIndex = this.setJson.index[updateJson.name];
let setItem = this.setJson.data[itemIndex];
if (setItem.primaryKey) {
delete dataJson.primaryKeyIndex[targetValue[setItem.name]];
dataJson.primaryKeyIndex[updateJson.value] = curIndex;
} else if (setItem.uni) {
delete dataJson.uniIndex[setItem.name][targetValue[setItem.name]];
dataJson.uniIndex[setItem.name][updateJson.value] = curIndex;
}
if (this.indexJsonMap[setItem.name]) {
delete dataJson.indexMap[setItem.name][targetValue[setItem.name]];
if (dataJson.indexMap[setItem.name][updateJson.value] instanceof Array) {
dataJson.indexMap[setItem.name][updateJson.value].push(curIndex);
} else {
dataJson.indexMap[setItem.name][updateJson.value] = [curIndex];
}
}
targetValue[updateJson.name] = updateJson.value;
dataJson.data[dataIndex] = targetValue;
}
dataJson.modify = 1;
modifyCount++;
if (modifyCount > 0) {
if (this.autoCommit) {
this.commit();
}
}
return modifyCount;
}
deleteDataByPathIndex({pathIndex, dataIndex}) {
if(typeof pathIndex != "number"){
throw("缺少参数pathIndex");
}
if(typeof dataIndex != "number"){
throw("缺少参数dataIndex");
}
let deleteCount = 0;
this.checkConnect();
let dataJson = this.dataJsonList[pathIndex];
this.loadDataJson(dataJson);
if (dataJson.data[dataIndex]) {
let targetValue = dataJson.data[dataIndex];
for (let setItem of this.setJson.data) {
if (setItem.primaryKey) {
delete dataJson.primaryKeyIndex[targetValue[setItem.name]];
} else if (setItem.uni) {
delete dataJson.uniIndex[setItem.name][targetValue[setItem.name]];
}
if (this.indexJsonMap[setItem.name]) {
let targetIndex = dataJson.indexMap[setItem.name][targetValue[setItem.name]].indexOf(curIndex);
if (targetIndex > -1) {
dataJson.indexMap[setItem.name][targetValue[setItem.name]].splice(targetIndex, 1);
}
}
dataJson.data[dataIndex] = {
__delete: 1
}
}
dataJson.modify = 1;
deleteCount++;
}
if (dataJson.modify) {
if (this.autoCommit) {
this.commit();
}
}
return deleteCount;
}
/**
* 删除数据
* @param {*} whereData {name:"列名",type:"比对类型",value:"值"}
*/
deleteData(whereData) {
let deleteCount = 0;
this.selectData(whereData, (dataJson, curIndex, targetValue) => {
dataJson.data[curIndex] = {
__delete: 1
};
dataJson.modify = 1;
for (let setItem of this.setJson.data) {
if (setItem.primaryKey) {
delete dataJson.primaryKeyIndex[targetValue[setItem.name]];
} else if (setItem.uni) {
delete dataJson.uniIndex[setItem.name][targetValue[setItem.name]];
}
if (this.indexJsonMap[setItem.name]) {
let targetIndex = dataJson.indexMap[setItem.name][targetValue[setItem.name]].indexOf(curIndex);
if (targetIndex > -1) {
dataJson.indexMap[setItem.name][targetValue[setItem.name]].splice(targetIndex, 1);
}
}
}
deleteCount++;
})
if (deleteCount > 0) {
if (this.autoCommit) {
this.commit();
}
}
return deleteCount;
}
loadDataJson(dataJson) {
if (!dataJson.read) {
let { data, primaryKeyIndex, uniIndex, indexMap } = this.readDataJson(dataJson.path);
dataJson.data = data;
dataJson.primaryKeyIndex = primaryKeyIndex;
dataJson.uniIndex = uniIndex;
dataJson.read = 1;
if (!indexMap) { indexMap = {}; }
dataJson.indexMap = indexMap;
let indexJsonMap = this.indexJsonMap;
for (let key in indexJsonMap) {
if (!indexMap[key]) {
indexMap[key] = {};
let index = 0;
for (let targetData in dataJson.data) {
if (!(indexMap[key][targetData[key]] instanceof Array)) { indexMap[key][targetData[key]] = [] }
indexMap[key][targetData[key]].push(index);
index++;
}
dataJson.modify = 1;
}
}
for (let key in indexMap) {
if (!indexJsonMap[key]) {
delete indexMap[key];
dataJson.modify = 1;
}
}
}
if (typeof dataJson.readCount != "number") {
dataJson.readCount = 0;
}
dataJson.readCount++;
if (dataJson.modify) {
this.saveDataJson({
data: dataJson.data,
path: dataJson.path,
primaryKeyIndex: dataJson.primaryKeyIndex,
uniIndex: dataJson.uniIndex,
indexMap: dataJson.indexMap || {}
});
}
}
/**
* 查询数据
* @param {*} whereData [{name:"列名",type:"比对类型",value:"值"}]
* @return 目前返回的都是对象,即实际是地址,不可以直接修改,需深拷贝后再直接修改,不然容易发生错误
*/
selectData(whereData, mapFun, limitData, orderByData) {
if (!(whereData instanceof Array)) {
throw ("whereData必须为数组");
}
this.checkConnect();
let resultSelect = [];
let setJson = this.setJson;
let { primaryKeyWhere, uniKeyWhere, indexKeyWhere, otherKeyWhere,
primaryEqualKeyWhere, uniEqualKeyWhere, indexEqualKeyWhere } = this.parseWhereArray(whereData, setJson);
for (let dataJson of this.dataJsonList) {
this.loadDataJson(dataJson);
this.filterAllWhere(dataJson, {
primaryKeyWhere, indexKeyWhere, otherKeyWhere, uniKeyWhere, primaryEqualKeyWhere, uniEqualKeyWhere, mapFun, indexEqualKeyWhere
}, resultSelect);
if ((!orderByData || orderByData.length == 0) && limitData && typeof limitData.count == "number") {
if (!limitData.start) {
limitData.start = 0;
}
if (resultSelect.length > limitData.start + limitData.count) {
resultSelect = resultSelect.slice(limitData.start, limitData.start + limitData.count);
break;
}
}
}
if (orderByData && orderByData.length > 0) {
resultSelect.sort((a, b) => {
for (let orderby of orderByData) {
if(a[orderby.name] != b[orderby.name]){
return orderby.type == "desc"?(b[orderby.name] - a[orderby.name]):(a[orderby.name] - b[orderby.name]);
}
}
if(a.__pathIndex != b.__pathIndex){
return a.__pathIndex - b.__pathIndex;
}
return a.__index - b.__index;
});
if (limitData && typeof limitData.count == "number") {
if (!limitData.start) {
limitData.start = 0;
}
resultSelect = resultSelect.slice(limitData.start, limitData.start + limitData.count);
}
}
return resultSelect;
}
filterAllWhere(dataJson, {
primaryKeyWhere, indexKeyWhere, indexEqualKeyWhere = [], otherKeyWhere,
uniKeyWhere, primaryEqualKeyWhere, uniEqualKeyWhere, mapFun
}, resultSelect) {
if (primaryEqualKeyWhere.value) {
let dataIndex = dataJson.primaryKeyIndex[primaryEqualKeyWhere.value];
if (typeof dataIndex == "number") {
let targetValue = dataJson.data[dataIndex];
if (targetValue && !targetValue.__delete) {
targetValue.__index = dataIndex;
targetValue.__pathIndex = dataJson.pathIndex;
if (this.checkValueWhere(targetValue, [...indexKeyWhere, ...indexEqualKeyWhere, ...uniKeyWhere, ...otherKeyWhere, ...primaryKeyWhere])) {
resultSelect.push(targetValue);
typeof mapFun == "function" && mapFun(dataJson, dataIndex, targetValue);
}
}
}
} else if (primaryKeyWhere.value) {
let primaryKeyIndex = dataJson.primaryKeyIndex;
let resultIndex = [];
for (let value in primaryKeyIndex) {
if (util.compare(value, primaryKeyWhere.type, primaryKeyWhere.value)) {
resultIndex.push(primaryKeyWhere[value]);
}
}
for (let dataIndex of resultIndex) {
let targetValue = dataJson.data[dataIndex];
if (targetValue && !targetValue.__delete) {
targetValue.__index = dataIndex;
targetValue.__pathIndex = dataJson.pathIndex;
if (this.checkValueWhere(targetValue, [...indexKeyWhere, ...indexEqualKeyWhere, ...uniKeyWhere, ...uniEqualKeyWhere, ...otherKeyWhere])) {
resultSelect.push(targetValue);
typeof mapFun == "function" && mapFun(dataJson, dataIndex, targetValue);
}
}
}
} else if (uniEqualKeyWhere.length > 0) {
let uniArrayIndex = undefined;
for (let uniWhere of uniEqualKeyWhere) {
let curUniIndex = dataJson.uniIndex[uniWhere.name][uniWhere.value];
if (typeof curUniIndex != "number") {
uniArrayIndex = undefined;
break;
}
if (uniArrayIndex == undefined) {
uniArrayIndex = curUniIndex;
} else {
if (uniArrayIndex != curUniIndex) {
uniArrayIndex = undefined;
break;
}
}
}
if (typeof uniArrayIndex == "number") {
let targetValue = dataJson.data[uniArrayIndex];
if (targetValue && !targetValue.__delete) {
targetValue.__index = uniArrayIndex;
targetValue.__pathIndex = dataJson.pathIndex;
if (this.checkValueWhere(targetValue, [...indexKeyWhere, ...indexEqualKeyWhere, ...uniKeyWhere, ...otherKeyWhere])) {
resultSelect.push(targetValue);
typeof mapFun == "function" && mapFun(dataJson, uniArrayIndex, targetValue);
}
}
}
} else if (uniKeyWhere.length > 0) {
let uniArrayIndex = undefined;
for (let uniWhere of uniKeyWhere) {
let curUniIndex = dataJson.uniIndex[uniWhere.name];
if (typeof curUniIndex == "undefined" || curUniIndex.length == 0) {
break;
}
let filterIndex = [];
for (let value in curUniIndex) {
if (util.compare(value, uniWhere.type, uniWhere.value)) {
filterIndex.push(curUniIndex[value]);
}
}
if (uniArrayIndex == undefined) {
uniArrayIndex = filterIndex;
continue;
} else {
uniArrayIndex = uniArrayIndex.filter(a => {
return filterIndex.indexOf(a) >= 0;
})
}
if (uniArrayIndex.length == 0) {
break;
}
}
if (uniArrayIndex && uniArrayIndex.length > 0) {
for (let index of uniArrayIndex) {
let targetValue = dataJson.data[index];
if (targetValue && !targetValue.__delete) {
targetValue.__index = index;
targetValue.__pathIndex = dataJson.pathIndex;
if (this.checkValueWhere(targetValue, [...indexEqualKeyWhere, ...indexKeyWhere, ...otherKeyWhere])) {
resultSelect.push(targetValue);
typeof mapFun == "function" && mapFun(dataJson, index, targetValue);
}
}
}
}
} else if (indexEqualKeyWhere.length > 0) {
let indexMap = dataJson.indexMap;
let curIndexArray = undefined;
for (let indexEqualKey of indexEqualKeyWhere) {
if (!indexMap[indexEqualKey.name]) {
continue;
}
if (!curIndexArray) {
curIndexArray = indexMap[indexEqualKey.name][indexEqualKey.value] || [];
} else {
let filterIndex = indexMap[indexEqualKey.name][indexEqualKey.value] || [];
curIndexArray = curIndexArray.filter(item => {
return filterIndex.indexOf(item) > -1;
})
}
}
if (curIndexArray && curIndexArray.length > 0) {
for (let curIndex of curIndexArray) {
let targetValue = dataJson.data[curIndex];
if (targetValue && !targetValue.__delete) {
targetValue.__index = curIndex;
targetValue.__pathIndex = dataJson.pathIndex;
if (this.checkValueWhere(targetValue, [...indexKeyWhere, ...otherKeyWhere])) {
resultSelect.push(targetValue);
typeof mapFun == "function" && mapFun(dataJson, curIndex, targetValue);
}
}
}
}
} else if (indexKeyWhere.length > 0) {
let resultIndex = undefined;
let indexMap = dataJson.indexMap;
for (let indexkey of indexKeyWhere) {
if (!indexMap[indexkey.name]) {
continue;
}
let indexMapValue = indexMap[indexkey.name];
for (let indexValue in indexMapValue) {
if (util.compare(indexValue, indexkey.type, indexkey.value)) {
if (resultIndex == undefined) {
resultIndex = indexMapValue[indexValue];
} else {
resultIndex = resultIndex.filter(item => {
return indexMapValue[indexValue].indexOf(item) > -1;
})
if (resultIndex.length == 0) {
resultIndex = [];
break;
}
}
}
}
}
if (resultIndex == undefined) {
//没有索引列,扫描全表
let curIndex = 0;
for (let targetValue of dataJson.data) {
if (targetValue && !targetValue.__delete) {
targetValue.__index = curIndex;
targetValue.__pathIndex = dataJson.pathIndex;
if (this.checkValueWhere(targetValue, [...indexKeyWhere, ...otherKeyWhere])) {
resultSelect.push(targetValue);
typeof mapFun == "function" && mapFun(dataJson, curIndex, targetValue);
}
}
curIndex++;
}
} else if (resultIndex.length > 0) {
//有索引 扫描索引
for (let curIndex of resultIndex) {
let targetValue = dataJson.data[curIndex];
if (targetValue && !targetValue.__delete) {
targetValue.__index = curIndex;
targetValue.__pathIndex = dataJson.pathIndex;
if (this.checkValueWhere(targetValue, [...otherKeyWhere])) {
resultSelect.push(targetValue);
typeof mapFun == "function" && mapFun(dataJson, curIndex, targetValue);
}
}
}
}
} else if (otherKeyWhere.length > 0) {
let curIndex = 0;
for (let targetValue of dataJson.data) {
if (targetValue && !targetValue.__delete) {
targetValue.__index = curIndex;
targetValue.__pathIndex = dataJson.pathIndex;
if (this.checkValueWhere(targetValue, [...otherKeyWhere])) {
resultSelect.push(targetValue);
typeof mapFun == "function" && mapFun(dataJson, curIndex, targetValue);
}
}
curIndex++;
}
} else {
let curIndex = 0;
for (let targetValue of dataJson.data) {
if (targetValue && !targetValue.__delete) {
targetValue.__index = curIndex;
targetValue.__pathIndex = dataJson.pathIndex;
resultSelect.push(targetValue);
typeof mapFun == "function" && mapFun(dataJson, curIndex, targetValue);
}
curIndex++;
}
}
}
checkValueWhere(value, whereArr) {
let result = true;
for (let item of whereArr) {
if (!util.compare(value[item.name], item.type, item.value)) {
result = false;
break;
}
}
return result;
}
/**
* 添加数据
* @param {*} itemData 添加的数据
*/
addData(itemData) {
this.checkConnect();
let setData = this.setJson.data;
if (!setData.autoIncrementIndex) {
setData.autoIncrementIndex = {};
}
let addJson = {};
let primaryKeyValue = undefined;
let uniList = [];
for (let item of setData) {
if (item.primaryKey) {
if (!itemData[item.name] && !item.autoIncrement) {
throw ("主键 " + item.name + " 不能为空")
} else if (!itemData[item.name]) {
primaryKeyValue = (setData.autoIncrementIndex[item.name] || 0) + 1;
setData.autoIncrementIndex[item.name] = primaryKeyValue;
itemData[item.name] = primaryKeyValue;
setData.modify = 1;
} else {
primaryKeyValue = itemData[item.name];
}
} else if (item.uni) {
if (!itemData[item.name]) {
throw ("唯一键 " + item.name + " 不能为空")
} else {
uniList.push({
name: item.name,
value: itemData[item.name]
});
}
} else if (item.autoIncrement && !itemData[item.name]) {
itemData[item.name] = (setData.autoIncrementIndex[item.name] || 0) + 1;
setData.autoIncrementIndex[item.name] = itemData[item.name];
setData.modify = 1;
}
if (itemData[item.name] && typeof itemData[item.name] != item.type) {
throw ("字段 " + item.name + " 类型不匹配 " + item.type)
}
if (typeof itemData[item.name] != "undefined") {
addJson[item.name] = itemData[item.name];
} else {
addJson[item.name] = item.default;
}
}
let curDataJson = this.getCurDataJson();
this.checkSaveValue(primaryKeyValue, uniList);
curDataJson.data.push(addJson);
let curAddIndex = curDataJson.data.length - 1;
if (typeof primaryKeyValue != "undefined") {
curDataJson.primaryKeyIndex[primaryKeyValue] = curAddIndex;
}
for (let uni of uniList) {
if (!curDataJson.uniIndex[uni.name]) {
curDataJson.uniIndex[uni.name] = {};
}
if (typeof uni.value != "undefined") {
curDataJson.uniIndex[uni.name][uni.value] = curAddIndex;
}
}
let indexMap = curDataJson.indexMap;
if (!indexMap) {
curDataJson.indexMap = {};
indexMap = curDataJson.indexMap;
}
for (let indexName in indexMap) {
if (indexMap[indexName]) {
indexMap[indexName].push(curAddIndex);
}
}
curDataJson.modify = 1;
if (this.autoCommit) {
this.commit();
if (this.setJson.modify == 1) {
this.saveSetJson();
}
}
}
/**
* 检查主键和唯一键是否冲突
* @param {*} primaryKeyValue 主键
* @param {*} uniList 唯一键 {键名:值}
*/
checkSaveValue(primaryKeyValue, uniList) {
if (!primaryKeyValue && !uniList) {
return;
}
let dataJsonList = this.dataJsonList;
for (let dataJson of dataJsonList) {
this.loadDataJson(dataJson);
if (typeof primaryKeyValue != "undefined" && typeof dataJson.primaryKeyIndex[primaryKeyValue] == "number") {
throw ("主键 " + value + " 已存在,请勿重复添加")
}
if (uniList instanceof Array) {
for (let uni of uniList) {
if (dataJson.uniIndex[uni.name] && typeof dataJson.uniIndex[uni.name][uni.value] == "number") {
throw ("唯一键 " + uni.name + " 值 " + uni.value + " 已存在,请勿重复添加")
}
}
}
if (!dataJson.readCount) {
dataJson.readCount = 1;
} else {
dataJson.readCount++;
}
}
}
/**
* 获取最新的数据对象
*/
getCurDataJson() {
if (this.dataJsonList.length == 0) {
let curDataJson = {
path: 'data_0.json',
data: [],
read: 1,
modify: 0,
primaryKeyIndex: {},
uniIndex: {}
};
this.dataJsonList.push(curDataJson);
return curDataJson;
}
let curDataJson = this.dataJsonList[this.dataJsonList.length - 1];
if (curDataJson.data.length >= MaxSaveLines) {
let curIndex = this.dataJsonList.length;
curDataJson = {
path: 'data_' + curIndex + '.json',
data: [],
read: 1,
modify: 0,
primaryKeyIndex: {},
uniIndex: {}
};
this.dataJsonList.push(curDataJson);
}
if (typeof curDataJson.readCount == "undefined") {
curDataJson.readCount = 0;
}
curDataJson.readCount++;
return curDataJson;
}
/**
* 提交数据
*/
commit() {
this.checkConnect();
this.doSaveDataJson();
}
/**
* 数据回滚 不保存
*/
rollback() {
this.checkConnect();
this.reloadDataJson();
}
/**
* 重载内存数据
*/
reloadDataJson() {
let dataJsonList = this.dataJsonList;
for (let dataJson of dataJsonList) {
dataJson.read = 0;
dataJson.modify = 0;
dataJson.data = [];
dataJson.readCount = 0;
dataJson.indexMap = {};
}
}
/**
* 释放最近不使用的内存数据
*/
releaseDataJson() {
let dataJsonList = this.dataJsonList;
if (dataJsonList.length <= releaseSaveCount) {
return;
}
if (releaseDataJsonTimeout) {
clearTimeout(releaseDataJsonTimeout)
}
releaseDataJsonTimeout = setTimeout(() => {
let readCountMap = [];
let index = 0;
for (let dataJson of dataJsonList) {
if (dataJson.read && dataJson.modify) {
index++;
continue;
}
readCountMap.push({
path: dataJson.path,
readCount: dataJson.readCount || 0,
index: index
})
index++;
}
readCountMap.sort((a, b) => {
if (a.readCount == b.readCount) {
return a.index - b.index;
}
return a.readCount - b.readCount;
})
for (let readIndex = 0; readIndex < readCountMap.length - releaseSaveCount; readIndex++) {
dataJsonList[readCountMap[readIndex].index].data = [];
dataJsonList[readCountMap[readIndex].index].modify = 0;
dataJsonList[readCountMap[readIndex].index].readCount = 0;
dataJsonList[readCountMap[readIndex].index].read = 0;
dataJsonList[readCountMap[readIndex].index].primaryKeyIndex = {};
dataJsonList[readCountMap[readIndex].index].uniIndex = {};
}
}, releaseLimitTime);
}
/** index 相关操作开始 */
loadTableIndex() {
this.checkConnect();
try {
let { data } = this.readIndexJson();
this.indexJsonMap = data;
} catch (e) {
util.log(e);
this.indexJsonMap = {};
this.saveIndexJson({ data: {} });
}
}
readIndexJson() {
let result = this.readFileSync('/index/index.json', {
data: {},
});
return result;
}
saveIndexJson(indexJson) {
this.fileManmger.writeFileSync({
filePath: this.CurPath + "/index/index.json",
data: JSON.stringify(indexJson),
encoding: "utf-8"
})
util.log("保存indexJson")
}
/**
* 添加索引
*/
alertAddIndex(name) {
this.checkConnect();
if (typeof this.setJson.index[name] != "number") {
throw ("不存在字段:" + name);
}
if (this.indexJsonMap[name]) {
throw ("已存在索引:" + name);
} else {
this.indexJsonMap[name] = 1;
}
this.doSaveIndexJson();
}
/**
* 删除索引
*/
dropIndex(name) {
this.checkConnect();
if (typeof this.setJson.index[name] != "number") {
throw ("不存在字段:" + name);
}
let curIndexJsonList = this.indexJsonMap[name];
if (typeof curIndexJsonList == "undefined") {
throw ("不存在索引:" + name);
}
delete this.indexJsonMap[name];
}
doSaveIndexJson() {
if (saveIndexJsonTimeout) {
clearTimeout(saveIndexJsonTimeout);
}
saveIndexJsonTimeout = setTimeout(() => {
this.saveIndexJson({ data: this.indexJsonMap });
}, saveLimitTime);
}
/** index 相关操作结束 */
deleteFile(path) {
this.fileManmger.unlinkSync({
filePath: path
})
}
parseWhereArray(whereData, setJson) {
let primaryKeyWhere = {};
let primaryEqualKeyWhere = {};
let uniKeyWhere = [];
let uniEqualKeyWhere = [];
let indexKeyWhere = [];
let otherKeyWhere = [];
let indexEqualKeyWhere = [];
for (let item of whereData) {
if (typeof setJson.index[item.name] != "number") {
throw ("不存在字段:" + item.name);
}
let curSetJson = setJson.data[setJson.index[item.name]];
if (curSetJson.primaryKey) {
if (item.type == "=") {
primaryEqualKeyWhere = item;
} else {
primaryKeyWhere = item;
}
} else if (curSetJson.uni) {
if (item.type == "=") {
uniEqualKeyWhere.push(item);
} else {
uniKeyWhere.push(item);
}
} else if (typeof this.indexJsonMap[item.name] != "undefined") {
if (item.type == "=") {
indexEqualKeyWhere.push(item);
} else {
indexKeyWhere.push(item);
}
} else {
otherKeyWhere.push(item);
}
}
return {
primaryKeyWhere,
uniKeyWhere,
indexKeyWhere,
otherKeyWhere,
uniEqualKeyWhere,
primaryEqualKeyWhere,
indexEqualKeyWhere
}
}
}
export default Table;
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