> > On Tuesday, November 22, 2022 at 10:16:11 AM EST, Erik Wienhold <e...@ewie.name> wrote: > > > > On 22/11/2022 15:23 CET Alastair McKinley <a.mckin...@analyticsengines.com> wrote: > > > > Hi all, > > > > I have come across this apparently common issue COPY-ing json and wondering if > > there is potentially a better solution. > > > > I am copying data into a jsonb column originating from a 3rd party API. The > > data may have literal \r,\t,\n and also double backslashes. > > > > I discovered that I can cast this data to a jsonb value directly but I can't > > COPY the data without pre-processing. > > > > Is there any other solution with COPY that doesn't require manual > > implementation of search/replace to handle these edge cases? > > Why does ::jsonb work but COPY doesn't? It seems a bit inconsistent. > > COPY handles special backslash sequences[1]. The \r in your sample JSON, > although properly escaped according to JSON, is replaced with an actual > carriage return by COPY before casting to jsonb. The error results from JSON > prohibiting unescaped control characters in strings[2]. > > You must double escape to pass those characters through COPY. > > See how COPY outputs backslash sequences: > > -- Actual carriage return: > copy (select e'\r') to stdout; > \r > > -- Backslash sequence for carriage return: > copy (select '\r') to stdout; > > \\r I have been able to get around this problem by using the following method:
\copy footable from 'input.json' (format csv, escape '^B', delimieter '^C', quote '^E') where the control characters are the actual control char, not the caret-letter, and it requires no escaping escapes. I realize this won't work for all situations. PJ > > [1] > https://www.postgresql.org/docs/current/sql-copy.html#id-1.9.3.55.9.2 > [2] https://www.json.org/json-en.html > > -- > Erik
