【报Bug】字节小程序 unicloud-db联表查询，多个临时表组成的数组的方法会报错，多个collection字符串拼接不会报错。

示例代码：

<template>  
       <!--不报错 -->  
    <!-- <unicloud-db ref="udb" v-slot:default="{data, loading, error,  options}" collection="book,author" where="name == '水浒传'"> -->  
<!--报错版本 -->  
  <unicloud-db v-slot:default="{data, loading, error, options}" :collection="colList">  
    <view v-if="error">{{error.message}}</view>  
    <view v-else-if="loading">正在加载...</view>  
    <view v-else>  
        {{data}}  
    </view>  
  </unicloud-db>  
</template>  
<script>  
  const db = uniCloud.database()  
  export default {  
    data() {  
      return {  
        colList: [  
          db.collection('book').where('name == "水浒传"').getTemp(),  
          db.collection('author').getTemp()  
        ]  
      }  
    },  
    onReady() {},  

    methods: {}  
  }  
</script>

操作步骤：

只要使用上述代码即可

预期结果：

不报错

实际结果：

**mp.runtime.esm.js?66fd:5634 TypeError: Cannot read property '0' of undefined**  
    at a.mainCollection (unicloud-db.vue?5078:170)  
    at Pr.get (mp.runtime.esm.js?66fd:4419)  
    at Pr.evaluate (mp.runtime.esm.js?66fd:4524)  
    at a.eval [as mainCollection] (mp.runtime.esm.js?66fd:4799)  
    at eval (mp.runtime.esm.js?66fd:5596)  
    at Array.reduce (<anonymous>)  
    at bo (mp.runtime.esm.js?66fd:5595)  
    at a.wo [as __patch__] (mp.runtime.esm.js?66fd:5632)  
    at a.e._update (mp.runtime.esm.js?66fd:3956)  
    at a.r (mp.runtime.esm.js?66fd:5700)  
    at Pr.get (mp.runtime.esm.js?66fd:4419)  
    at new Pr (mp.runtime.esm.js?66fd:4408)  
    at xo (mp.runtime.esm.js?66fd:5706)  
    at a.Gr.$mount (mp.runtime.esm.js?66fd:6039)  
    at Object.__lifetimes_attached (index.js?f266:2336)  
    at Object.r.lifetimes.attached (index.js?f266:2341)  
wo @ mp.runtime.esm.js?66fd:5634  
e._update @ mp.runtime.esm.js?66fd:3956  
r @ mp.runtime.esm.js?66fd:5700  
Pr.get @ mp.runtime.esm.js?66fd:4419  
Pr @ mp.runtime.esm.js?66fd:4408  
xo @ mp.runtime.esm.js?66fd:5706  
Gr.$mount @ mp.runtime.esm.js?66fd:6039  
__lifetimes_attached @ index.js?f266:2336  
r.lifetimes.attached @ index.js?f266:2341  
t.tryCatch @ VM138:16  
eval @ VM138:16  
n.callComponentLifetime @ VM138:16  
n.attached @ VM138:16  
eval @ VM138:16  
qc.emit @ VM138:2  
eval @ VM138:2  
subscribeHandler @ VM138:2  
invokeService @ C:\Program Files\@bytedminiprogram-ide\resources\app\extensions\miniprogram-extension\node_modules\@byted\miniprogram-simulator\public\shell\preload\bgWebviewPreload.js:129  
(anonymous) @ C:\Program Files\@bytedminiprogram-ide\resources\app\extensions\miniprogram-extension\node_modules\@byted\miniprogram-simulator\public\shell\preload\bgWebviewPreload.js:432  
(anonymous) @ C:\Program Files\@bytedminiprogram-ide\resources\app\extensions\miniprogram-extension\node_modules\@byted\miniprogram-simulator\public\shell\preload\bgWebviewPreload.js:1  
emit @ events.js:327  
onMessage @ electron/js2c/renderer_init.js:91  
appInit.js:73 onDBError {code: "SYNTAX_ERROR", message: "查询语句存在错误，请检查传入的临时表是否正确"}  
appInit.js:78 SYNTAX_ERROR 查询语句存在错误，请检查传入的临时表是否正确  
f @ appInit.js:78  
eval @ index.js?a9ff:1  
value @ index.js?a9ff:1  
eval @ index.js?a9ff:1  
unicloud-db.vue?5078:561 Error: 查询语句存在错误，请检查传入的临时表是否正确  
    at eval (index.js?a9ff:1)