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HPL/SQL is included to Apache Hive since version 2.0

copy

COPY Statement

COPY statement allows to transfer data between tables and files. Use it to transfer relatively small volumes of data i.e. query results, look-up and dimension tables.

When you copy data between tables they can be located in different databases.

Syntax:

Export data to a file:

COPY table_name | (select_stmt) TO [HDFS] file_name [options]
 
options:
  DELIMITER 'char'
| SQLINSERT target_table_name

Copy data between existing tables:

COPY table_name | (select_stmt) TO target_table_name AT target_conn_name [options]
 
options:
  BATCHSIZE num

Notes:

  • table_name is an identifier.
  • file_name can be an expression, quoted or unquoted string.
  • If file_name already exists it is overwritten.
  • When HDFS is specified, the data is copied to a HDFS-compatible file system.
  • DELIMITER specifies the delimiter between column values, '\t' (TAB character) is the default.
  • SQLINSERT specifies to generate SQL INSERT statements to insert data to target_table_name. The statements are just stored in the file, and not executed.
  • When you copy data into another table, the table must exist.
  • BATCHSIZE specifies the number of rows to transfer in a single batch when copying rows between tables, the default is 1000.

Example 1:

Export the query results to a file:

COPY (SELECT id, name FROM sales.users WHERE local_dt = CURRENT_DATE) 
  TO /data/users.txt DELIMITER '\t';

Example 2:

Generate SQL INSERT statements:

COPY sales.users TO /data/users2.sql SQLINSERT sales.users;

Example 3:

Copy rows from between tables in different databases:

COPY sales.users TO sales.users2 AT tdconn;

Compatibility: HPL/SQL Extension, PostgreSQL

Version: HPL/SQL 0.3.7

See also: