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DP columns are specified the same way as it is for SP columns – in the partitin-partition clause. The only difference is that DP columns do not have values, while SP columns havedo. In the partition - clause, we need to specify all partitioning columns, even though if all of them are DP columns.

In INSERT ... SELECT ... queries, the dynamic partition columns must be specified last among the columns in the select statement and in the order of the directory hierarchy in which the table data are stored (i.e., normally in the order in which the partitions were declared in the CREATE TABLE statement).

• all DP columns – only allowed in nonstrict mode. In strict mode, we should throw an error. e.g.,

  Code Block
  INSERT OVERWRITE TABLE T PARTITION (ds, hr) SELECT key, value, ds, hr FROM srcpart WHERE ds is not null and hr>10;

• mixed SP & DP columns. e.g.,

  Code Block
  INSERT OVERWRITE TABLE T PARTITION (ds='2010-03-03', hr) SELECT key, value, /*ds,*/ hr FROM srcpart WHERE ds is not null and hr>10;

• SP is a subpartition of a DP: should throw an error because partition column order determins directory hierarchy. We cannot change the hierarchy in DML. e.g.,

  Code Block
  -- throw an exception INSERT OVERWRITE TABLE T PARTITION (ds, hr = 11) SELECT key, value, ds/*, hr*/ FROM srcpart WHERE ds is not null and hr=11;

• multi-table insert. e.g.,

  Code Block
  FROM S INSERT OVERWRITE TABLE T PARTITION (ds='2010-03-03', hr) SELECT key, value, ds, hr FROM srcpart WHERE ds is not null and hr>10 INSERT OVERWRITE TABLE R PARTITION (ds='2010-03-03, hr=12) SELECT key, value, ds, hr from srcpart where ds is not null and hr = 12;

• CTAS – syntax is a little bit different from CTAS on non-partitioned tables, since
  the schema of the target table is not totally derived from the select-clause.
  We need to specify the schema including partitioning columns in the
  create-clause. e.g.,

  Code Block
  CREATE TABLE T (key int, value string) PARTITIONED BY (ds string, hr int) AS SELECT key, value, ds, hr+1 hr1 FROM srcpart WHERE ds is not null and hr>10;

  The above example shows the case of all DP columns in CTAS. If you want put
  some constant for some partitioning column, you can specify it in the
  select-clause. e.g,

  Code Block
  CREATE TABLE T (key int, value string) PARTITIONED BY (ds string, hr int) AS SELECT key, value, "2010-03-03", hr+1 hr1 FROM srcpart WHERE ds is not null and hr>10;

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