SQLite3 UNIQUE constraint failed error : <p>I am trying to create a database which allows users to create 'to do' lists and fill them with items to complete. However, when inserting data into the tables it gives me a UNIQUE constraint failed error and I don't know how to solve it. This is my code for creating the database and inserting data.</p>

<pre><code>CREATE TABLE user (
    user_id integer  NOT NULL   PRIMARY KEY,
    first_name varchar(15)  NOT NULL,
    title varchar(5)  NOT NULL,
    username varchar(15)  NOT NULL,
    password varchar(20)  NOT NULL,
    email varchar(50)  NOT NULL,
    bio text  NOT NULL
);


CREATE TABLE list (
    list_id integer  NOT NULL   PRIMARY KEY,
    list_name varchar(10)  NOT NULL,
    user_user_id integer  NOT NULL,
    FOREIGN KEY (user_user_id) REFERENCES user(user_id)
);


CREATE TABLE item (
    item_id integer  NOT NULL   PRIMARY KEY,
    item text  NOT NULL,
    completed boolean  NOT NULL,
    list_list_id integer  NOT NULL,
    FOREIGN KEY (list_list_id) REFERENCES list(list_id)
);


-- Data:
INSERT INTO user VALUES (1, "Name1", "Title1", "Username1", "Password1", "Email1", "Bio1");
INSERT INTO user VALUES (2, "Name2", "Title2", "Username2", "Password2", "Email2", "Bio2");
INSERT INTO user VALUES (3, "Name3", "Title3", "Username3", "Password3", "Email3", "Bio3");

INSERT INTO list VALUES (1, "user1-list1", 1);
INSERT INTO list VALUES (2, "user1-list2", 1);
INSERT INTO list VALUES (3, "user1-list3", 1);
INSERT INTO list VALUES (1, "user2-list1", 2);
INSERT INTO list VALUES (1, "user3-list1", 3);
INSERT INTO list VALUES (2, "user3-list2", 3);

INSERT INTO item VALUES (1, "user1-list1-item1", "FALSE", 1);
INSERT INTO item VALUES (2, "user1-list1-item2", "FALSE", 1);
INSERT INTO item VALUES (1, "user1-list2-item1", "FALSE", 2);
INSERT INTO item VALUES (1, "user1-list3-item1", "FALSE", 3);
INSERT INTO item VALUES (2, "user1-list3-item2", "FALSE", 3);
INSERT INTO item VALUES (1, "user2-list1-item1", "FALSE", 1);
INSERT INTO item VALUES (2, "user2-list1-item1", "FALSE", 1);
INSERT INTO item VALUES (1, "user3-list1-item1", "FALSE", 1);
INSERT INTO item VALUES (1, "user3-list3-item1", "FALSE", 2);
</code></pre>

<p>I have copied the errors I receive below:</p>

<pre><code>Error: near line 43: UNIQUE constraint failed: list.list_id
Error: near line 44: UNIQUE constraint failed: list.list_id
Error: near line 45: UNIQUE constraint failed: list.list_id
Error: near line 49: UNIQUE constraint failed: item.item_id
Error: near line 50: UNIQUE constraint failed: item.item_id
Error: near line 51: UNIQUE constraint failed: item.item_id
Error: near line 52: UNIQUE constraint failed: item.item_id
Error: near line 53: UNIQUE constraint failed: item.item_id
Error: near line 54: UNIQUE constraint failed: item.item_id
Error: near line 55: UNIQUE constraint failed: item.item_id
</code></pre>

<p>Any help would be appreciated!</p>
