如何从shell脚本向.sql文件传递参数

Question

Hi there if anyone can help me, I have a .sh script that executes 4 .sql scripts, each executing against a schema. Currently the schema name is hardcoded but i want to make it configurable.

Given the following below how will i pass the arguments from the shell script to the .files?

an eg call to a .sql is done in my shell script is done so like the following

ECHO “DELETING SCHEME….”
psql -f $SCRIPT_DIR/delete_data.sql my_db postgres
ECHO “DATABASE SCHEMA DELETED..”

delete_data.sql

drop schema my_schema cascade;
create schema my_schema;

Answer 1

You could replace the my_schema part with a placeholder, like %SCHEMA% :

drop schema %SCHEMA% cascade;
create schema %SCHEMA%;

We then run a substitution using sed , and pipe the results into psql (reading from stdin is equivalent to reading from file):

sed "s/%SCHEMA%/$schemaName/" $SCRIPT_DIR/delete_data.sql | psql powa_aim_db postgres

Answer 2

You can do this using a heredoc for your SQL:

my_schema="$1"
ECHO “DELETING SCHEME….”
psql <<SQL
drop schema $my_schema cascade
create schema $my_schema
SQL
ECHO “DATABASE SCHEMA DELETED..”

Then call your script with the schema name as the first argument:

$ ./my_script my_schema_name