Question

更新：通过更新ID序列中的lastval解决了该问题

SELECT pg_catalog.setval('public.products_product_id_seq', max(id), false);

其中max(id)是select max(id) from products_product

我的数据库在mysql上，当我尝试使用多种工具将其导入postgresql时，它多次失败。

我决定为每个表导出csvs，然后使用COPY将它们导入postgres。

COPY products_product(id, name, unit_price, timestamp, updated, description, 
category_id, minimum_stock, qrcode, stock, unit, owner_id) 
FROM '~/csv/products.csv' DELIMITER ';' CSV HEADER;

导入后，无论使用哪种视图，我都可以更新我的所有模型（我也尝试过在管理员身上进行操作）。

但是，当我尝试创建一个新对象（与哪个对象无关）时，我得到一个IntegrityError，例如：null value in column "id" violates not-null constraint。（也曾在管理员上试过）。

在我所有的模型和所有视图中，问题都是相同的，这使我相信导入后的postgres数据库一定存在问题（也许是主键计数器？）。因为在运行迁移之后并且导入任何东西之前，我就能够创建对象。

如何解决此问题？在postgres上是否有配置或必须更改的内容？或者我不知道的有关Django的内容？

如果您对我的模型感到好奇：

class Product(models.Model):
    name = models.CharField(
        max_length=120,
        null=False,
        blank=False,
        verbose_name='Nombre')
    description = models.TextField(
        blank=True,
        null=True,
        verbose_name='Descripción')
    category = models.ForeignKey(
        'Category',
        on_delete=models.SET_NULL,
        null=True,
        blank=True,
        verbose_name='Categoría')
    unit_price = models.PositiveIntegerField(
        default=0,
        null=False,
        blank=False,
        verbose_name='Precio unitario')
    unit = models.CharField(
        max_length=255,
        default='ud',
        blank=True)
    image = models.ImageField(
        upload_to='images/products',
        blank=True,
        null=True,
        verbose_name='Imagen')
    qrcode = models.ImageField(
        upload_to='qrcode',
        blank=True,
        null=True)
    stock = models.IntegerField(default=0)
    minimum_stock = models.PositiveIntegerField(default=0)

    owner = models.ForeignKey(
        'users.Company',
        on_delete=models.CASCADE,
        related_name='products')
    timestamp = models.DateTimeField(
        default=timezone.now,
        null=True)
    updated = models.DateTimeField(
        auto_now=True,
        null=True)

    def __str__(self):
        return self.name

我的postgress表如下：

Table "public.products_product"
    Column     |           Type           | Collation | Nullable |         Default         
---------------+--------------------------+-----------+----------+-------------------------
 id            | integer                  |           | not null | 
 name          | character varying(120)   |           | not null | NULL::character varying
 description   | text                     |           |          | 
 unit_price    | integer                  |           | not null | 
 unit          | character varying(255)   |           | not null | NULL::character varying
 image         | character varying(100)   |           |          | 
 qrcode        | character varying(100)   |           |          | NULL::character varying
 stock         | integer                  |           | not null | 
 minimum_stock | integer                  |           | not null | 
 timestamp     | timestamp with time zone |           |          | 
 updated       | timestamp with time zone |           |          | 
 category_id   | integer                  |           |          | 
 owner_id      | integer                  |           | not null | 1
Indexes:
    "products_product_pkey" PRIMARY KEY, btree (id)
    "products_product_category_id_9b594869" btree (category_id)
    "products_product_owner_id_f189d068" btree (owner_id)
Check constraints:
    "products_product_minimum_stock_check" CHECK (minimum_stock >= 0)
    "products_product_unit_price_check" CHECK (unit_price >= 0)
Foreign-key constraints:
    "products_product_category_id_9b594869_fk_products_category_id" FOREIGN KEY (category_id) REFERENCES products_category(id) DEFERRABLE INITIALLY DEFERRED
    "products_product_owner_id_f189d068_fk_users_company_id" FOREIGN KEY (owner_id) REFERENCES users_company(id) DEFERRABLE INITIALLY DEFERRED
Referenced by:
    TABLE "expenses_item" CONSTRAINT "expenses_item_product_id_551c230a_fk_products_product_id" FOREIGN KEY (product_id) REFERENCES products_product(id) DEFERRABLE INITIALLY DEFERRED
    TABLE "orders_item" CONSTRAINT "orders_item_product_id_260e6ee8_fk_products_product_id" FOREIGN KEY (product_id) REFERENCES products_product(id) DEFERRABLE INITIALLY DEFERRED
    TABLE "quotations_item" CONSTRAINT "quotations_item_product_id_fa055ee8_fk_products_product_id" FOREIGN KEY (product_id) REFERENCES products_product(id) DEFERRABLE INITIALLY DEFERRED

和示例csv数据：

"id";"name";"unit_price";"timestamp";"updated";"description";"category_id";"minimum_stock";"qrcode";"stock";"unit";"owner_id"
1;"Tote bag";1;"2018-07-24 17:05:37.631487";"2018-12-24 17:05:37.631487";"";;0;"";0;"ud";1
4;"Canvas bag";280;"2018-07-29 22:43:58.015396";"2018-12-29 22:43:58.015396";"";;0;"";0;"ud";1
5;"T-shirt";400;"2018-07-29 22:44:39.847575";"2018-12-29 22:45:06.463699";"";;0;"";0;"ud";1

Answer 1

您可以尝试从postgres复制命令中删除id，并从csv中删除ID。喜欢

COPY products_product(name, unit_price, timestamp, updated, description, 
category_id, minimum_stock, qrcode, stock, unit, owner_id) 
FROM '~/csv/products.csv' DELIMITER ';' CSV HEADER;

将数据库导入Postgresql后，“ id”列中的IntegrityError空值

1 个答案: