Problems while importing a txt file into postgres using php

Question

I am trying to import a txt/csv file into my postgres database from php using "\copy" command. I cannot use COPY instead of \copy as I need it to execute as a psql client. My code is:

$query = '\\'.'copy data1 FROM "data1.txt" WITH CSV HEADER DELIMITER AS "," QUOTE AS "^"';

$result = pg_query($conn,$query);
if (!$result) {
  echo "cannot copy data\n";
} else {
  echo "SUCCESS!";
}

When I run this php file, I get this error:

PHP Warning:  pg_query(): Query failed: ERROR:  syntax error at or near "\"
LINE 1: \copy data1 FROM "data1.txt" WITH ...
    ^ in script.php on line 30

Answer 1

You cannot run \copy via pg_query(). It is not an SQL command. It is a meta-command of the psql client.

There you can execute:

\copy data1 FROM 'data1.txt' WITH CSV HEADER DELIMITER AS ',' QUOTE AS '^'

Or run the shell-command:

psql mydb -c "\copy data1 FROM 'data1.txt'
                WITH CSV HEADER DELIMITER AS ',' QUOTE AS '^'"

Note the quotes. Values need to be single-quoted in PostgreSQL: 'value'.
Double-quotes are for identifiers - and are only actually needed for identifiers with upper case or illegal character or for reserved words: "My table".

Answer 2

I encountered the same problem, but instead of using the the raw psql \copy command, decided to use the Ecto.Adapters.SQL.stream/2 function to read the contents of the file, and Repo.transaction/1 that executes the normal SQL COPY command getting the data from STDIN provided by the stream as described in this blog. I haven't tested the performance of this but i figured it would be a good addition to this answer.