Postgres Inner Join Select query returns error: column does not exist

Question

I have been reading through the documentation and I can't find what I'm doing wrong here. I'm executing this query: ``` SELECT * FROM "parts" INNER JOIN "categories" ON "categories"."id" = "parts"."category_id" WHERE "categories"."name" = "cars" ``` And I'm getting this error: ``` ERROR: column "cars" does not exist LINE 3: WHERE (categories.name = "cars") ^ ********** Error ********** ERROR: column "cars" does not exist SQL state: 42703 Character: 122 ``` Category Table: ``` CREATE TABLE categories ( id serial NOT NULL, name character varying(255), CONSTRAINT categories_pkey PRIMARY KEY (id) ) ``` Parts Table: ``` CREATE TABLE parts ( id serial NOT NULL, category_id integer, CONSTRAINT parts_pkey PRIMARY KEY (id) ) ``` Any help would be greatly appreciated.

Accepted Answer

You should use single apostrophes for string constants:

```
SELECT *
FROM "parts"
INNER JOIN "categories" ON "categories"."id" = "parts"."category_id"
WHERE "categories"."name" = 'cars'
```

The doubles mean db objects.(fields, tables, etc.)

(Otherwise they are not necessary, only for extras, for example spaces in names etc.)

Postgres Inner Join Select query returns error: column does not exist

Solution

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