Postgres COPY with command strips escapes from JSON file (Also loads each line as seperate row)

问题

If I have the following json file

C:\PostgresStage>type test2.json
{"key":"Hello \"World\""}

And I try to load it into a json or text column using the COPY command I end up with invalid JSON because copy appears to strip the escape characters from the file as can be seen below

postgres=# \d+ T1
                               Table "public.t1"
Column | Type | Collation | Nullable | Default | Storage  | Stats target | Description
--------+------+-----------+----------+---------+----------+--------------+-------------
 data   | text |           |          |         | extended |              |


postgres=# delete from T1;
DELETE 1
postgres=# copy t1 from 'c:\PostgresStage\test2.json';
COPY 1
postgres=# select  * from T1;
          data
-------------------------
 {"key":"Hello "World""}
 (1 row)


postgres=# select data::jsonb from T1;
ERROR:  invalid input syntax for type json
DETAIL:  Token "World" is invalid.
CONTEXT:  JSON data, line 1: {"key":"Hello "World...
postgres=#

Is there anyway to prevent this..

Also if I have 'pretty' JSON such as this

C:\PostgresStage>type test2.json
{
  "key":"Hello \"World\""
}

It gets loaded as 3 rows. Is there anyway to use copy to load the entire file as one row.

Finally is there anyway to use COPY to pass a parameter to a function rather than load a row into a table

回答1:

For JSON documents that are not "pretty printed", eg the entire document is a single line in the file, a hack is to use

 copy t1 from 'c:\PostgresStage\test2.json' csv quote e'\x01' delimiter e'\x02';

Thanks to http://adpgtech.blogspot.com/2014/09/importing-json-data.html

来源：https://stackoverflow.com/questions/52334512/postgres-copy-with-command-strips-escapes-from-json-file-also-loads-each-line-a