[IMPALA-813] Executing INSERT OVERWRITE from JDBC Inserts Zero Records

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Duplicate
• Affects Version/s: Impala 1.2.3
• Fix Version/s: Impala 1.3
• Environment: impalad version 1.2.3 RELEASE (build 1cab04cdb88968a963a8ad6121a2e72a3a623eca); CentOS release 6.5 (kernel 2.6.32-431.3.1.el6.x86_64); Java 1.7.0_21-b11
• Assignee: Alan Choi
• Reporter: Tom Wheeler
• Created: 18/Feb/14 08:04
• Updated: 20/Dec/15 00:05
• Resolved: 18/Feb/14 17:34

Description

While using JDBC, I have observed that creating and populating a table based on another table results in a new table that contains zero records. Issuing the same SQL statements through impala-shell populates the target table as expected.

Here is the overview of what I found:

0. I open a connection to Impala via JDBC for the subsequent steps

1. I create a new table (prospects) using tab-delimited text format

2. I populate the prospects table with 5000 records.

3. Using a CREATE TABLE .. AS SELECT or a CREATE TABLE .. LIKE (the latter being followed by INSERT INTO or INSERT OVERWRITE), I attempt to populate the new table using data from original table. There is no visible exception, so I am led to believe that it worked OK.

4. I issue a SELECT statement (with no WHERE or LIMIT clause) against the new table, but no records are returned.

5. I switch to impala-shell and issue the exact same INSERT OVERWRITE statement from step 2. It reports that 5000 rows were inserted.

6. Using JDBC again, I issue the exact same SELECT statement from step 4 and it returns all the records I expected.

I have attached two classes that demonstrate the problem (TableDataGenerator just populates the table; CreateAndQueryTableClient is the one you should run). Although I used parquet format for the target table, I can reproduce the problem with a target table in text file format.