How do I call Oracle or MySQL sql statements in UNIX / Linux shell scripts?

MySQL: Use SQL Directly In Shell Scripts
#!/bin/sh
user="dbuser"
pass="dbpassword"
db="dbnme"
mysql -u "$user" -p"$pass" "$db" <<EOF
  sql-statement-1;
  sql-statement-2;
EOF
Using Shell Variables In SQL
#!/bin/sh
user="dbuser"
pass="dbpassword"
db="dbnme"
sql="select * from tal_name"
mysql -u "$user" -p"$pass"  <<EOF
  use $db;
  $sql;
EOF
Oracle: Use SQL Directly In Shell Scripts
#!/bin/sh
user="system"
pass="manager"
sqlplus -S $user/$pass <<EOF
  sql-statement-1;
  sql-statement-2;
 exit;
EOF
Using Shell Variables In SQL
#!/bin/sh
user="system"
pass="manager"
var="$1"
sqlplus -S $user/$pass <<EOF
 SELECT * FROM tableName WHERE username=$var;
 exit;
EOF
You can call sql statements from .sql file itself as follows:
#!/bin/ksh
sqlplus -S system/manager @my_sql_script.sql