Fix migration package name mismatch

db/migrations/20200819111809_drop_email_unique_constraint.go

@@ -0,0 +1,43 @@
+package migrations
+
+import (
+	"context"
+	"database/sql"
+
+	"github.com/pressly/goose/v3"
+)
+
+func init() {
+	goose.AddMigrationContext(upDropEmailUniqueConstraint, downDropEmailUniqueConstraint)
+}
+
+func upDropEmailUniqueConstraint(_ context.Context, tx *sql.Tx) error {
+	_, err := tx.Exec(`
+create table user_dg_tmp
+(
+	id varchar(255) not null
+		primary key,
+	user_name varchar(255) default '' not null
+		unique,
+	name varchar(255) default '' not null,
+	email varchar(255) default '' not null,
+	password varchar(255) default '' not null,
+	is_admin bool default FALSE not null,
+	last_login_at datetime,
+	last_access_at datetime,
+	created_at datetime not null,
+	updated_at datetime not null
+);
+
+insert into user_dg_tmp(id, user_name, name, email, password, is_admin, last_login_at, last_access_at, created_at, updated_at) select id, user_name, name, email, password, is_admin, last_login_at, last_access_at, created_at, updated_at from user;
+
+drop table user;
+
+alter table user_dg_tmp rename to user;
+`)
+	return err
+}
+
+func downDropEmailUniqueConstraint(_ context.Context, tx *sql.Tx) error {
+	return nil
+}