Change IAP migration for cockroachdb support

-- +migrate Up

ALTER TABLE purchase_receipt

    ADD PRIMARY KEY (transaction_id),

    DROP CONSTRAINT purchase_receipt_pkey,

    DROP COLUMN receipt,

    ADD COLUMN environment SMALLINT NOT NULL DEFAULT 0; -- Unknown(0), Sandbox(1), Production(2)

    DROP CONSTRAINT IF EXISTS purchase_receipt_pkey, -- Drop primary key constraint for Postgres

    DROP CONSTRAINT IF EXISTS "primary",             -- Drop primary key constraint for Cockroach

    ADD CONSTRAINT purchase_receipt_pkey PRIMARY KEY (transaction_id);

-- +migrate Down

ALTER TABLE purchase_receipt

    ADD COLUMN receipt TEXT NOT NULL CHECK (length(receipt) > 0),

    ADD COLUMN IF NOT EXISTS receipt TEXT NOT NULL CHECK (length(receipt) > 0),

    DROP CONSTRAINT purchase_receipt_pkey,

    ADD PRIMARY KEY (receipt),

    DROP COLUMN environment;

    ADD CONSTRAINT purchase_receipt_pkey PRIMARY KEY (receipt);

/*

 * Copyright 2020 The Nakama Authors

 *

 * Licensed under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 *

 * http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

-- +migrate Up

ALTER TABLE purchase_receipt

    ADD COLUMN environment SMALLINT NOT NULL DEFAULT 0, -- Unknown(0), Sandbox(1), Production(2)

    DROP COLUMN IF EXISTS receipt;

-- +migrate Down

ALTER TABLE purchase_receipt

    ADD COLUMN IF NOT EXISTS receipt TEXT NOT NULL CHECK (length(receipt) > 0),

    DROP COLUMN IF EXISTS environment;