Updated on 2022-12-07 GMT+08:00

Exporting Search Results

Function

This statement is used to directly write query results to a specified directory. The query results can be stored in CSV, Parquet, ORC, JSON, or Avro format.

Syntax

1
2
3
4
INSERT OVERWRITE DIRECTORY path
  USING file_format
  [OPTIONS(key1=value1)]
  select_statement;

Keyword

  • USING: Specifies the storage format.
  • OPTIONS: Specifies the list of attributes to be exported. This parameter is optional.

Parameter

Table 1 INSERT OVERWRITE DIRECTORY parameter description

Parameter

Description

path

The OBS path to which the query result is to be written.

file_format

Format of the file to be written. The value can be CSV, Parquet, ORC, JSON, or Avro.

If the file format is set to CSV, see the Table 3 for the OPTIONS parameters.

Precautions

  • You can configure the spark.sql.shuffle.partitions parameter to set the number of files to be inserted into the OBS bucket in the table. In addition, to avoid data skew, you can add distribute by rand() to the end of the INSERT statement to increase the number of concurrent jobs. The following is an example:
    insert into table table_target select * from table_source distribute by cast(rand() * N as int);
  • When the configuration item is OPTIONS('DELIMITER'=','), you can specify a separator. The default value is ,.

    For CSV data, the following delimiters are supported:

    • Tab character, for example, 'DELIMITER'='\t'.
    • Any binary character, for example, 'DELIMITER'='\u0001(^A)'.
    • Single quotation mark ('). A single quotation mark must be enclosed in double quotation marks (" "). For example, 'DELIMITER'= "'".

Example

1
2
3
4
INSERT OVERWRITE DIRECTORY 'obs://bucket/dir'
  USING csv
  OPTIONS(key1=value1)
  select * from db1.tb1;