Why Does My PostgreSQL INSERT Statement Fail with 'ERROR: column 'user2' does not exist'?

Unable to Insert Data: Error "ERROR: column "value" does not exist"

When attempting to insert data into the "users" table using the following query:

INSERT INTO users (user_name, name, password,email) 
    VALUES ("user2", "first last", "password1", "[email protected]");

users encounter an error message stating: "ERROR: column "user2" does not exist." This error indicates that the column specified in the query ("user2") does not match any existing column in the "users" table.

Upon examining the table schema, we notice that the "user_name" column is defined as a "character varying(50)", which means it accepts textual data. However, in our query, we are attempting to insert the string "user2" without enclosing it in single quotes. This is where the error arises.

Correct Query Using Single Quotes:

According to PostgreSQL convention, character constants require single quotes to be enclosed within. Therefore, the corrected query should be:

INSERT INTO users(user_name, name, password,email) VALUES ('user2','first last','password1', '[email protected]' );

By enclosing the "user2" value in single quotes, we are explicitly indicating to PostgreSQL that this is a character constant and not a column name.

Additional Notes:

• Refer to the PostgreSQL documentation for further clarification on character constants: postgresql.org/docs/current/static/datatype-character.html
• Exercise caution when using double quotes with PostgreSQL, as they are typically reserved for identifiers (e.g., table names, column names). Using double quotes for character constants can lead to unexpected errors.

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