multiline cat " << EOF"

Examples of cat <<EOF syntax usage in Bash:

1. Assign multi-line string to a shell variable

$ sql=$(cat <<EOF
SELECT foo, bar FROM db
WHERE foo='baz'
EOF
)

The $sql variable now holds the new-line characters too. You can verify with echo -e "$sql".

2. Pass multi-line string to a file in Bash

$ cat <<EOF > print.sh
#!/bin/bash
echo \$PWD
echo $PWD
EOF

The print.sh file now contains:

#!/bin/bash
echo $PWD
echo /home/user

3. Pass multi-line string to a pipe in Bash

$ cat <<EOF | grep 'b' | tee b.txt
foo
bar
baz
EOF