I m trying to import a txt file into a postgresql table. However, in the txt data, there is a value including newline.
When exporting txt file, I can change row seperator different than "\n" but i couldnt find any parameter to change row seperator for copy command.
OS: linux
Is there a row seperator parameter for copy command in postgresql?
Example:
Txt file:( delimiter "|")
1st line:
ab|dc|blabla|ef
2nd line:
ab|dc|bla
bla|ef
In the second row , third column include bla (newline) bla.
Postgres command:
copy tablename from 'a.txt' with delimiter '|' null '';
Related
There is a text field in a Postgres database containing new lines. I would like to export the content of that field to a text file, preserving those new lines. However, the COPY TO command explictly transforms those characters into the \n string. For example:
$ psql -d postgres -c "COPY (SELECT CHR(10)) TO '/tmp/out.txt';"
COPY 1
$ cat /tmp/out.txt
\n
This behaviour seems to match the short description in the documents:
Presently, COPY TO will never emit an octal or hex-digits backslash sequence, but it does use the other sequences listed above for those control characters.
Is there any workaround to get the new line in the output? E.g. that a command like:
$ psql -d postgres -c "COPY (SELECT 'A line' || CHR(10) || 'Another line') TO '/tmp/out.txt';"
Results in something like:
A line
Another line
Update: I do not wish to obtain a CSV file. The output must not have headers, column separators or column decorators such as quotes (exactly as exemplified in the output above). The answers provided in a different question with COPY AS CSV do not fulfil this requirement.
Per my comment:
psql -d postgres -U postgres -c "COPY (SELECT CHR(10)) TO '/tmp/out.txt' WITH CSV;"
Null display is "NULL".
COPY 1
cat /tmp/out.txt
"
"
psql -d postgres -U postgres -c "COPY (SELECT 'A line' || CHR(10) || 'Another line') TO '/tmp/out.txt' WITH CSV;"
Null display is "NULL".
COPY 1
cat /tmp/out.txt
"A line
Another line"
Using the CSV format will maintain the embedded line breaks in the output. This is explained here COPY under CSV Format
The values in each record are separated by the DELIMITER character. If the value contains the delimiter character, the QUOTE character, the NULL string, a carriage return, or line feed character, then the whole value is prefixed and suffixed by the QUOTE character, and any occurrence within the value of a QUOTE character or the ESCAPE character is preceded by the escape character. You can also use FORCE_QUOTE to force quotes when outputting non-NULL values in specific columns.
...
Note
CSV format will both recognize and produce CSV files with quoted values containing embedded carriage returns and line feeds. Thus the files are not strictly one line per table row like text-format files.
UPDATE
Alternate method that does not involve quoting, using psql.
create table line_wrap(id integer, fld_1 varchar);
insert into line_wrap values (1, 'line1
line2');
insert into line_wrap values (2, 'line3
line4');
select fld_1 from line_wrap
\g (format=unaligned tuples_only=on) out.txt
cat out.txt
line1
line2
line3
line4
I have the three statements below that all work until it hits a row with an extra tab at the end of the tab delimited text file that I am trying to import.
Any way to tell Postgres to ignore extra tabs?
copy mara FROM 'c:/Postgres MME/AG00_MARA.txt' DELIMITER E'\t' NULL '' CSV HEADER;
copy mara FROM 'c:/Postgres MME/AG00_MARA.txt' DELIMITER E'\t' CSV HEADER;
copy mara FROM 'c:/Postgres MME/AG00_MARA.txt' WITH (FORMAT csv, DELIMITER E'\t', NULL '', HEADER);
Image of Notepad++ Where I see the extra tab at the end of the row
Don't try to ignore it, just fix your data by removing all the trailing tabs with regex \t$. For example in Linux:
sed -i 's/\t$//g' AG00_MARA.txt
I was trying to import a CSV file into a PostgreSQL table using the COPY command. The delimiter of the CSV file is comma (,). However, there's also a text field with a comma in the value. For example:
COPY schema.table from '/folder/foo.csv' delimiter ',' CSV header
Here's the content of the foo.csv file:
Name,Description,Age
John,Male\,Tall,30
How to distinguish between the literal comma and the delimiter?
Thanks for your help.
To have the \ to be recognized as a escape character it is necessary to use the text format
COPY schema.table from '/folder/foo.csv' delimiter ',' TEXT
But then it is also necessary to delete the first line as the HEADER option is only valid for the CSV format.
I have my simple CSV file, delimited by commas and no strange character, and when trying to do a \COPY table FROM '/srv/www/.../CSV.csv' WITH DELIMITER ',' I get the error
ERROR: literal newline found in data
HINT: Use "\n" to represent newline.
Its not the first time I execute a COPY and it never happened to me. I exported the CSV from excel to Notepad and saved here as CSV (I know some programs add extra info, but AFAIK notepad does not)
If you want to import CSV, you must specify FORMAT CSV. A literal newline is not legal in PostgreSQL's default delimited input.
\COPY table FROM '/srv/www/.../CSV.csv' WITH (FORMAT CSV, DELIMITER ',');
When I try to export the text content of a field, and that content have carriage return characters, that chars are output like \N string.
For example:
create table foo ( txt text );
insert into foo ( txt ) values ( 'first line
second line
...
and other lines');
copy foo ( txt ) to '/tmp/foo.txt';
I want to return the following (a):
first line
second line
...
and other lines
But, output is (b):
first line\Nsecond line\N...\Nand other lines
Anybody knows how to get the (a) output?
The \N comes from the fact that one line must correspond to one database row.
This rule is relaxed for the CSV format where multi-line text is possible but then a quote character (by default: ") would enclose the text.
If you want multi-line output and no enclosing character around it, you shouldn't use COPY but SELECT.
Assuming a unix shell as the execution environment of the caller, you could do:
psql -A -t -d dbname -c 'select txt from foo' >/tmp/file.txt
Have you tried: \r\n?
Here's another solution that might work:
E'This is the first part \\n And this is the second'
via https://stackoverflow.com/a/938/1085891
Also, rather than copy the other responses, see here: String literals and escape characters in postgresql