ref/copy

ref/copy

Loading COPY Formatted Files

This commands instructs pgloader to load from a file containing COPY TEXT data as described in the PostgreSQL documentation. Here’s an example:

LOAD COPY
     FROM copy://./data/track.copy
          (
            trackid, track, album, media, genre, composer,
            milliseconds, bytes, unitprice
          )
     INTO postgresql:///pgloader
   TARGET TABLE track_full

     WITH truncate

      SET work_mem to '14MB',
          standard_conforming_strings to 'on'

BEFORE LOAD DO
     $$ drop table if exists track_full; $$,
     $$ create table track_full (
          trackid      bigserial,
          track        text,
          album        text,
          media        text,
          genre        text,
          composer     text,
          milliseconds bigint,
          bytes        bigint,
          unitprice    numeric
        );
     $$;

The COPY format command accepts the following clauses and options.

COPY Formatted Files Source Specification: FROM

Filename where to load the data from. This support local files, HTTP URLs and zip files containing a single dbf file of the same name. Fetch such a zip file from an HTTP address is of course supported.

  • inline

    The data is found after the end of the parsed commands. Any number of empty lines between the end of the commands and the beginning of the data is accepted.

  • stdin

    Reads the data from the standard input stream.

  • FILENAMES MATCHING

    The whole matching clause must follow the following rule:

    [ ALL FILENAMES | [ FIRST ] FILENAME ]
    MATCHING regexp
    [ IN DIRECTORY '...' ]
    

    The matching clause applies given regular expression (see above for exact syntax, several options can be used here) to filenames. It’s then possible to load data from only the first match of all of them.

    The optional IN DIRECTORY clause allows specifying which directory to walk for finding the data files, and can be either relative to where the command file is read from, or absolute. The given directory must exists.

COPY Formatted File Options: WITH

When loading from a COPY file, the following options are supported:

  • delimiter

    Takes a single character as argument, which must be found inside single quotes, and might be given as the printable character itself, the special value t to denote a tabulation character, or 0x then an hexadecimal value read as the ASCII code for the character.

    This character is used as the delimiter when reading the data, in a similar way to the PostgreSQL COPY option.

  • null

    Takes a quoted string as an argument (quotes can be either double quotes or single quotes) and uses that string as the NULL representation in the data.

    This is similar to the null COPY option in PostgreSQL.

  • truncate

    When this option is listed, pgloader issues a TRUNCATE command against the PostgreSQL target table before reading the data file.

  • disable triggers

    When this option is listed, pgloader issues an ALTER TABLE … DISABLE TRIGGER ALL command against the PostgreSQL target table before copying the data, then the command ALTER TABLE … ENABLE TRIGGER ALL once the COPY is done.

    This option allows loading data into a pre-existing table ignoring the foreign key constraints and user defined triggers and may result in invalid foreign key constraints once the data is loaded. Use with care.

  • skip header

    Takes a numeric value as argument. Instruct pgloader to skip that many lines at the beginning of the input file.