Add Send A Command To psql as a postgres til.

README.md

@@ -65,6 +65,7 @@ smart people at [Hashrocket](http://hashrocket.com/).
 - [Intervals Of Time By Week](postgres/intervals-of-time-by-week.md)
 - [Limit Execution Time Of Statements](postgres/limit-execution-time-of-statements.md)
 - [List All Columns Of A Specific Type](postgres/list-all-columns-of-a-specific-type.md)
+- [Send A Command To psql](postgres/send-a-command-to-psql.md)
 - [String Contains Another String](postgres/string-contains-another-string.md)
 - [Temporarily Disable Triggers](postgres/temporarily-disable-triggers.md)
 - [Temporary Tables](postgres/temporary-tables.md)

postgres/send-a-command-to-psql.md

@@ -0,0 +1,23 @@
+# Send A Command To psql
+
+You can send a command to `psql` to be executed by using the `-c` flag
+
+```bash
+$ psql -c "select 'Hello, World!';"
+   ?column?
+---------------
+ Hello, World!
+(1 row)
+```
+
+Specify a particular database as needed
+
+```bash
+$ psql blog_prod -c 'select count(*) from posts;'
+ count 
+-------
+     8 
+(1 row)
+```
+
+h/t Jack Christensen