src/contrib/sqoop/doc/hive.txt

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Importing Data Into Hive
------------------------

Sqoop's primary function is to upload your data into files in HDFS. If
you have a Hive metastore associated with your HDFS cluster, Sqoop can
also import the data into Hive by generating and executing a +CREATE
TABLE+ statement to define the data's layout in Hive. Importing data
into Hive is as simple as adding the *+--hive-import+* option to your
Sqoop command line.

After your data is imported into HDFS, Sqoop will generate a Hive
script containing a +CREATE TABLE+ operation defining your columns using
Hive's types, and a +LOAD DATA INPATH+ statement to move the data files
into Hive's warehouse directory. The script will be executed by
calling the installed copy of hive on the machine where Sqoop is run.
If you have multiple Hive installations, or +hive+ is not in your
+$PATH+ use the *+--hive-home+* option to identify the Hive installation
directory. Sqoop will use +$HIVE_HOME/bin/hive+ from here.

NOTE: This function is incompatible with +--as-sequencefile+.

Hive's text parser does not know how to support escaping or enclosing
characters. Sqoop will print a warning if you use +--escaped-by+,
+--enclosed-by+, or +--optionally-enclosed-by+ since Hive does not know
how to parse these. It will pass the field and record terminators through
to Hive. If you do not set any delimiters and do use +--hive-import+,
the field delimiter will be set to +^A+ and the record delimiter will
be set to +\n+ to be consistent with Hive's defaults.

Hive's Type System
~~~~~~~~~~~~~~~~~~

Hive users will note that there is not a one-to-one mapping between
SQL types and Hive types. In general, SQL types that do not have a
direct mapping (e.g., +DATE+, +TIME+, and +TIMESTAMP+) will be coerced to
+STRING+ in Hive. The +NUMERIC+ and +DECIMAL+ SQL types will be coerced to
+DOUBLE+. In these cases, Sqoop will emit a warning in its log messages
informing you of the loss of precision.