How to solve the problem of Android target:not installed in cordova requirements?

ask for advice, how to solve this error?

E:\cordova-demo>cordova requirements
Android Studio project detected

Requirements check results for android:
Java JDK: installed 1.8.0
Android SDK: installed true

Android target: not installed
cmd: Command failed with exit code 1 Error output:
"avdmanager" 


Gradle: installed C:\Program Files\Android\Android Studio\gradle\gradle-4.4\bin\gradle
(node:20108) UnhandledPromiseRejectionWarning: CordovaError: Some of requirements check failed
    at C:\Users\Nan.Yuan\AppData\Roaming\npm\node_modules\cordova\src\cli.js:414:27
    at _fulfilled (C:\Users\Nan.Yuan\AppData\Roaming\npm\node_modules\cordova\node_modules\cordova-lib\node_modules\q\q.js:787:54)
    at self.promiseDispatch.done (C:\Users\Nan.Yuan\AppData\Roaming\npm\node_modules\cordova\node_modules\cordova-lib\node_modules\q\q.js:816:30)
    at Promise.promise.promiseDispatch (C:\Users\Nan.Yuan\AppData\Roaming\npm\node_modules\cordova\node_modules\cordova-lib\node_modules\q\q.js:749:13)
    at C:\Users\Nan.Yuan\AppData\Roaming\npm\node_modules\cordova\node_modules\cordova-lib\node_modules\q\q.js:557:44
    at flush (C:\Users\Nan.Yuan\AppData\Roaming\npm\node_modules\cordova\node_modules\cordova-lib\node_modules\q\q.js:108:17)
    at _combinedTickCallback (internal/process/next_tick.js:131:7)
    at process._tickCallback (internal/process/next_tick.js:180:9)
(node:20108) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejection id: 1)
(node:20108) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

when I installed it for the first time, I looked confused. Ask for advice


it doesn't matter because the android virtual machine is not installed, but it is actually debugged with the real machine most of the time, so this error can be ignored.

MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1c285d2-338d5.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1c285d2-338d5.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
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