Hui Huang created HIVE-20284:
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             Summary: In strict mode, if constant propagation is enable, the 
partition filter is folded before partition pruner lead to error "No partition 
predicate for Alias"  
                 Key: HIVE-20284
                 URL: https://issues.apache.org/jira/browse/HIVE-20284
             Project: Hive
          Issue Type: Improvement
          Components: CLI
    Affects Versions: 1.2.1, 2.3.3
            Reporter: Hui Huang
            Assignee: Hui Huang
             Fix For: 2.3.3


In strict mode and the hive.optimize.constant.propagation is set to true, the 
following sql will failed:

{code:java}
hive> desc employee_part;
OK
col_name        data_type       comment
eid                     int
name                    string
dept                    string
year                    string
month                   string

# Partition Information
# col_name              data_type               comment

year                    string
month                   string
Time taken: 0.564 seconds, Fetched: 11 row(s)
hive> set hive.mapred.mode=strict;
hive> select * from employee_part where false and concat(year,month)='201807';
FAILED: SemanticException Queries against partitioned tables without a 
partition filter are disabled for safety reasons. If you know what you are 
doing, please sethive.strict.checks.large.query to false and that 
hive.mapred.mode is not set to 'strict' to proceed. Note that if you may get 
errors or incorrect results if you make a mistake while using some of the 
unsafe features. No partition predicate for Alias "employee_part" Table 
"employee_part"
{code}

The above error msg is confusing,  concat(year,month)='201807' is the partition 
filter。

The reason is during logic optimization, the ConstantPropagate optimizer is 
running before partitionPruner optimizer, when found a express like 'false and 
concat(year,month)=xxxx', the express will replace with 'fasle' and the 
partition filter is droped. So the PartitionPruner can not get the partition 
filter.

Users can remove the constant express that always has true/false values to work 
around.

When views used, if some columns are constant values, users  will be  confusing.

So we should add some more message in the error msg returned.




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