Practical SQL Handbook, The: Using SQL Variants, Fourth Edition

Displaying Two Columns as One

Another function (concatenate) allows you to put expressions together. It is represented as a double pipe (||). The syntax looks like this:

char_expr || char_expr

For example, you can concatenate first and last names into one string:

SQL

select au_fname  || au_lname as Writer
from authors
where state > 'CA'
Writer
========================================================
AlbertRinger
AnneRinger
MichelDeFrance
SylviaPanteley
MorningstarGreene
Innesdel Castillo
ReginaldBlotchet-Halls
MeanderSmith
[8 rows]

To make the names more readable, add a space in quotes after the first name and another concatenation symbol after the space:

SQL

select au_fname || ' '  || au_lname as Writer from authors where state > 'CA' Writer ...