数据分析——Hive数据库初始化失败Error: FUNCTION 'NUCLEUS_ASCII' already exists.

进入Hive交互系统，“show databases：”。出现报错：

Failed to start database 'metastore_db' with class loader sun.misc.Launcher$AppClassLoader

经查找是因为数据库初始化的问题。

进入终端初始化数据库

[hadoop@master apache-hive-3.1.1-bin]$ ./bin/schematool -dbType derby -initSchema

报错：

Metastore Connection Driver :     org.apache.derby.jdbc.EmbeddedDriver
Metastore connection User:     APP
Starting metastore schema initialization to 3.1.0
Initialization script hive-schema-3.1.0.derby.sql

 
Error: FUNCTION 'NUCLEUS_ASCII' already exists. (state=X0Y68,code=30000)
org.apache.hadoop.hive.metastore.HiveMetaException: Schema initialization FAILED! Metastore state would be inconsistent !!
Underlying cause: java.io.IOException : Schema script failed, errorcode 2
Use --verbose for detailed stacktrace.
*** schemaTool failed ***

解决：删除apache-hive-3.1.1-bin文件夹下的metastore_db文件

[hadoop@master apache-hive-3.1.1-bin]$ rm -rf metastore_db

重新初始化数据库，进入hive交互模式show databases；成功。