psql shell command execution with \!

Question

Is there any way to capture shell output (in a psql variable) and/or the exit code of running a shell command from inside psql using \\! ? The documentation provides no details.

Answer 1

Seems to be impossible for \\! ,

but one can set a variable from external command output,

testdb=> \set content `cat my_file.txt`

and then using this var in sql expression like this:

testdb=> INSERT INTO my_table VALUES (:'content');

Answer 2

您可以使用\\o <filename>选项指定输出文件或使用COPY 命令来解决您的问题。

Answer 3

Using \\! with \\o ..

You can combine the two like this,

• \\! echo "SELECT 1;" > bar \\! echo "SELECT 1;" > bar (runs the command echo "SELECT 1;" redirects output of SELECT 1; to bar )
• \\o bar (runs the commands in bar )