How to pipe multiple sql- and py-scripts

Question

I have the following code copied from github gtfs_SQL_importer:

cat gtfs_tables.sql \
  <(python import_gtfs_to_sql.py path/to/gtfs/data/directory) \
  gtfs_tables_makeindexes.sql \
  vacuumer.sql \
  | psql mydbname

I tried to run this on windows and replaced the call to the UNIX-command cat by the windows equivalent type which should work similar as of is-there-replacement-for-cat-on-windows.

However when I execute that code I get some error:

The syntax for the filename, directory or filesystem is wrong.

So I tried to limit the number of piped files to only combine the call to python and the call to psql:

type <(C:/python27/python path/to/py-script.py path/to/file-argument) | psql -U myUser -d myDatabase

which results in the same error.

However when I execute the python-script alone it works as expected:

C:/python27/python path/to/py-script.py path/to/file-argument

So I assume the error results from using type in order to pipe the result of the script directly to psql.

Does anyone know the correct syntax?

EDIT: To ensure the problem is not related to a file not being found I used absolute paths for all arguments within my command except the type and the psql-command (which are both handled via the %PATH%-variable).

Are you sure that your syntax is correct? You have a redirection operator directly after `type`. Could you try to do: `type gtfs_tables.sql <(C:/python27/python path/tp/py-script.py path/to/file-argument) | psql -U myUser -d myDataBase`? — puelo, Jun 13 '17 at 20:27
as of http://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/redirection.mspx?mfr=true the `<`-command should read data from my python-script and send it to the pipe (in my case to `psql`). However I also added the first sql-file before the `<` which yields to the same message. — MakePeaceGreatAgain, Jun 13 '17 at 20:35
What is the output of just this part `type <(C:/python27/python path/to/py-script.py path/to/file-argument)`? — zenlc2000, Jun 14 '17 at 00:53
As I remember, <() operator is bash-specific, not even POSIX-specific. It will hardly work on Windows. — newtover, Jun 19 '17 at 10:42

score 4 · Answer 1 · answered Jun 20 '17 at 03:52

4

Install cygwin and use unix cat on Windows.

answered Jun 20 '17 at 03:52

matt2000

1,064
11
17

score 2 · Accepted Answer · edited Jan 30 '22 at 07:29

Comment: So I can´t combine the sql-files and the output from my pythonscript together and pipe them to psql?

Another approach, create your own cat with Python, or add the first three line of code to import_gtfs_to_sql.py, for instance:

# Usage
python import_gtfs_to_sql.py... | python myCat.py gtfs_tables.sql | psql mydbname

#myCat.py
import sys
with open(sys.argv[1]) as fh:
    sys.stdout.write(fh.read())

sys.stdout.write(sys.stdin.read())

Comment: I already know the error comes from type<(python...)

TYPE command does not accept stdin.

Therefore your only solution is Option 2.

Another approach is to use your Python Script to do print gtfs_tables.sql.

Question: the syntax for the filename, directory or filesystem is wrong.

Find out from which part the above Error comes from.

 a) type gtfs_tables.sql
 b) type <(python ...   
 c) type gtfs_tables.sql <(python ...  
 d) type gtfs_tables.sql | psql mydbname
 e) type <(python ... | psql mydbname

Save the Output of <(python ... to a File and try

 python ... > tmp_python_output
 type gtfs_tables.sql tmp_python_output | psql mydbname

I allready know the error comes from `type<(python...)`. Thus your answer doesn´t solve the problem at all. — MakePeaceGreatAgain, Jun 14 '17 at 19:10
"TYPE command does not accept stdin." So I can´t combine the sql-files and the output from my pythonscript together and pipe them to psql? Sad, but thanks for the hint. — MakePeaceGreatAgain, Jun 17 '17 at 13:47

How to pipe multiple sql- and py-scripts

2 Answers2