THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
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The inputs contain both the tables and the partitions. Note that the table is present even if none of the partitions is accessed in the query.
The dependencies show the parents in case a table is accessed via a view. Consider the following queries:
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CREATE VIEW V1 AS SELECT key, value from src;
EXPLAIN DEPENDENCY SELECT * FROM V1;
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The following output is produced:
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{"input_partitions":[],"input_tables":[{"tablename":"default@v1","tabletype":"VIRTUAL_VIEW"},{"tablename":"default@src","tabletype":"MANAGED_TABLE","tableParents":"[default@v1]"}]}
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As above, the inputs contain the view V1 and the table 'src' that the view V1 refers to.
All the outputs are shown if a table is being accessed via multiple parents.
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CREATE VIEW V2 AS SELECT ds, key, value FROM srcpart WHERE ds IS NOT NULL;
CREATE VIEW V4 AS
SELECT src1.key, src2.value as value1, src3.value as value2
FROM V1 src1 JOIN V2 src2 on src1.key = src2.key JOIN src src3 ON src2.key = src3.key;
EXPLAIN DEPENDENCY SELECT * FROM V4;
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The following output is produced.
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{"input_partitions":[{"partitionParents":"[default@v2]","partitionName":"default<at:var at:name="srcpart" />ds=2008-04-08/hr=11"},{"partitionParents":"[default@v2]","partitionName":"default<at:var at:name="srcpart" />ds=2008-04-08/hr=12"},{"partitionParents":"[default@v2]","partitionName":"default<at:var at:name="srcpart" />ds=2008-04-09/hr=11"},{"partitionParents":"[default@v2]","partitionName":"default<at:var at:name="srcpart" />ds=2008-04-09/hr=12"}],"input_tables":[{"tablename":"default@v4","tabletype":"VIRTUAL_VIEW"},{"tablename":"default@v2","tabletype":"VIRTUAL_VIEW","tableParents":"[default@v4]"},{"tablename":"default@v1","tabletype":"VIRTUAL_VIEW","tableParents":"[default@v4]"},{"tablename":"default@src","tabletype":"MANAGED_TABLE","tableParents":"[default@v4, default@v1]"},{"tablename":"default@srcpart","tabletype":"MANAGED_TABLE","tableParents":"[default@v2]"}]}
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As can be seen, src is being accessed via parents v1 and v4.