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sqlpostgresqlunique-constraint

How do I ALTER a PostgreSQL table and make a column unique?

I have a table in PostgreSQL where the schema looks like this:

CREATE TABLE "foo_table" (
    "id" serial NOT NULL PRIMARY KEY,
    "permalink" varchar(200) NOT NULL,
    "text" varchar(512) NOT NULL,
    "timestamp" timestamp with time zone NOT NULL
)

Now I want to make the permalink unique across the table by ALTER-ing the table.

Solution

  • I figured it out from the PostgreSQL docs, the exact syntax is:

    ALTER TABLE the_table ADD CONSTRAINT constraint_name UNIQUE (thecolumn);

    Thanks Fred.