With just 3 records, the data is cluttered with duplicate information. +-+-+-+-+-+-+-Ĥ | John Smith | f | 19:01:52.341599 | Chaos | What is the butterfly effect? | 5 | 2 Market Streetĥ | Jane Smith | t | 19:05:55.439876 | Simple Taoism | About Living in balance | 5 | 3 Market StreetĦ | Jane Smith | t | 19:08:06.039351 | The Storyteller | Memories of WWII | 4 | 3 Market Street Id | username | enabled | last_login | book_title | review_content | rating | address Let's see what the data looks like library=# SELECT * FROM users VALUES('Jane Smith', true, 'The Storyteller', 'Memories of WWII', 4, '3 Market Street') INSERT into users(username, enabled,book_title, review_content,rating,address) VALUES('Jane Smith', true, 'Simple Taoism', 'About Living in balance', 5, '3 Market Street') INSERT into users(username, enabled, book_title, review_content, rating, address)
VALUES('John Smith', false, 'Chaos', 'What is the butterfly effect?', 5, '2 Market Street') Next, we need to insert some data into the table INSERT into users(username, enabled, book_title, review_content, rating, address) Last_login | timestamp without time zone | not null default now() Username | character varying(25) | not null Id | integer | not null default nextval('users_id_seq'::regclass) First we need to add these columns using the ALTER TABLE command. We could start adding these pieces to the users table, resulting in a table with many columns. In this chapter we want to add several more pieces of data to our database. We'll still be working with the familiar library database and users table from previous chapters, but with a blank users table to start with. Follow the directions above in the info box to retrieve starter data for this chapter. With that in mind, we'll start fresh in this chapter. In the chapter on altering a table, we ended up changing our users database in various ways. If the table doesn't exist, PostgreSQL will ignore the command and move on to executing the rest of the backup file. These are included in case that table already exists. There are some commands in place at the start of the backup file for altering and removing the users table. When running the above command, you may see the following message: ERROR: relation "ers" does not exist.
#Pgadmin 4 use schema create table download
First download the backup file for this chapter from here. The library database can be restored from a backup file. The library database is needed to work through this chapter's content. If you don't already have a database named "library", then make sure to run createdb library from the terminal before starting this chapter.
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