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https://issues.apache.org/jira/browse/HIVE-16907?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16084245#comment-16084245
 ] 

Bing Li commented on HIVE-16907:
--------------------------------

[~pxiong] and [~lirui], thank you for your comments.
I tried CREATE TABLE statement in MySQL, and found that it treats the `db.tbl` 
as the table name. And "dot" is allowed in the table name. 
e.g.

{code:java}
mysql> create table xxx (col int);
mysql> create table test.yyy (col int);
mysql> create table `test.zzz` (col int);
mysql> create table `test.test.tbl` (col int);

mysql> show tables;
+----------------+
| Tables_in_test |
+----------------+
| test.test.tbl  |
| test.zzz       |
| xxx            |
| yyy            |
+----------------+
{code}

Back to Hive, if we would like to make it having the same behavior as MySQL, we 
should change the logic of processing it.
My previous patch is NOT enough and can't handle `db.db.tbl` neither.

>  "INSERT INTO"  overwrite old data when destination table encapsulated by 
> backquote 
> ------------------------------------------------------------------------------------
>
>                 Key: HIVE-16907
>                 URL: https://issues.apache.org/jira/browse/HIVE-16907
>             Project: Hive
>          Issue Type: Bug
>          Components: Parser
>    Affects Versions: 1.1.0, 2.1.1
>            Reporter: Nemon Lou
>            Assignee: Bing Li
>         Attachments: HIVE-16907.1.patch
>
>
> A way to reproduce:
> {noformat}
> create database tdb;
> use tdb;
> create table t1(id int);
> create table t2(id int);
> explain insert into `tdb.t1` select * from t2;
> {noformat}
> {noformat}
> +---------------------------------------------------------------------------------------------------------------------------------------------------+
> |                                                                      
> Explain                                                                      |
> +---------------------------------------------------------------------------------------------------------------------------------------------------+
> | STAGE DEPENDENCIES:                                                         
>                                                                       |
> |   Stage-1 is a root stage                                                   
>                                                                       |
> |   Stage-6 depends on stages: Stage-1 , consists of Stage-3, Stage-2, 
> Stage-4                                                                      |
> |   Stage-3                                                                   
>                                                                       |
> |   Stage-0 depends on stages: Stage-3, Stage-2, Stage-5                      
>                                                                       |
> |   Stage-2                                                                   
>                                                                       |
> |   Stage-4                                                                   
>                                                                       |
> |   Stage-5 depends on stages: Stage-4                                        
>                                                                       |
> |                                                                             
>                                                                       |
> | STAGE PLANS:                                                                
>                                                                       |
> |   Stage: Stage-1                                                            
>                                                                       |
> |     Map Reduce                                                              
>                                                                       |
> |       Map Operator Tree:                                                    
>                                                                       |
> |           TableScan                                                         
>                                                                       |
> |             alias: t2                                                       
>                                                                       |
> |             Statistics: Num rows: 0 Data size: 0 Basic stats: NONE Column 
> stats: NONE                                                             |
> |             Select Operator                                                 
>                                                                       |
> |               expressions: id (type: int)                                   
>                                                                       |
> |               outputColumnNames: _col0                                      
>                                                                       |
> |               Statistics: Num rows: 0 Data size: 0 Basic stats: NONE Column 
> stats: NONE                                                           |
> |               File Output Operator                                          
>                                                                       |
> |                 compressed: false                                           
>                                                                       |
> |                 Statistics: Num rows: 0 Data size: 0 Basic stats: NONE 
> Column stats: NONE                                                         |
> |                 table:                                                      
>                                                                       |
> |                     input format: 
> org.apache.hadoop.hive.ql.io.RCFileInputFormat                                
>                                   |
> |                     output format: 
> org.apache.hadoop.hive.ql.io.RCFileOutputFormat                               
>                                  |
> |                     serde: 
> org.apache.hadoop.hive.serde2.columnar.ColumnarSerDe                          
>                                          |
> |                     name: tdb.t1                                            
>                                                                       |
> |                                                                             
>                                                                       |
> |   Stage: Stage-6                                                            
>                                                                       |
> |     Conditional Operator                                                    
>                                                                       |
> |                                                                             
>                                                                       |
> |   Stage: Stage-3                                                            
>                                                                       |
> |     Move Operator                                                           
>                                                                       |
> |       files:                                                                
>                                                                       |
> |           hdfs directory: true                                              
>                                                                       |
> |           destination: 
> hdfs://hacluster/user/hive/warehouse/tdb.db/t1/.hive-staging_hive_2017-06-15_15-52-34_017_849305017872068583-1/-ext-10000
>   |
> |                                                                             
>                                                                       |
> |   Stage: Stage-0                                                            
>                                                                       |
> |     Move Operator                                                           
>                                                                       |
> |       tables:                                                               
>                                                                       |
> |           replace: true                                                     
>                                                                       |
> |           table:                                                            
>                                                                       |
> |               input format: org.apache.hadoop.hive.ql.io.RCFileInputFormat  
>                                                                       |
> |               output format: 
> org.apache.hadoop.hive.ql.io.RCFileOutputFormat                               
>                                        |
> |               serde: org.apache.hadoop.hive.serde2.columnar.ColumnarSerDe   
>                                                                       |
> |               name: tdb.t1                                                  
>                                                                       |
> |                                                                             
>                                                                       |
> |   Stage: Stage-2                                                            
>                                                                       |
> |     Merge File Operator                                                     
>                                                                       |
> |       Map Operator Tree:                                                    
>                                                                       |
> |           RCFile Merge Operator                                             
>                                                                       |
> |       merge level: block                                                    
>                                                                       |
> |       input format: org.apache.hadoop.hive.ql.io.RCFileInputFormat          
>                                                                       |
> |                                                                             
>                                                                       |
> |   Stage: Stage-4                                                            
>                                                                       |
> |     Merge File Operator                                                     
>                                                                       |
> |       Map Operator Tree:                                                    
>                                                                       |
> |           RCFile Merge Operator                                             
>                                                                       |
> |       merge level: block                                                    
>                                                                       |
> |       input format: org.apache.hadoop.hive.ql.io.RCFileInputFormat          
>                                                                       |
> |                                                                             
>                                                                       |
> |   Stage: Stage-5                                                            
>                                                                       |
> |     Move Operator                                                           
>                                                                       |
> |       files:                                                                
>                                                                       |
> |           hdfs directory: true                                              
>                                                                       |
> |           destination: 
> hdfs://hacluster/user/hive/warehouse/tdb.db/t1/.hive-staging_hive_2017-06-15_15-52-34_017_849305017872068583-1/-ext-10000
>   |
> |                                                                             
>                                                                       |
> +---------------------------------------------------------------------------------------------------------------------------------------------------+
> {noformat}
> Note that  'replace: true'  in move operator



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