Question

我正在尝试生成一个catalog表，这样每次我添加到其他2个表时它都是相同的id。目前，我必须运行多个查询来生成。只是想尝试简化它。这是我的原始查询，任何合并的想法都值得赞赏！

update equipment_needed
set  `catalog_id` = (select `id` from equipment_catalog where item_name = '32g bins')
where item_name = '32g bins';

update equipment_needed
set  `catalog_id` = (select `id` from equipment_catalog where item_name = 'Collection Bags')
where item_name = 'Collection Bags';

update equipment_needed
set  `catalog_id` = (select `id` from equipment_catalog where item_name = 'Chicken Wire Bins')
where item_name = 'Chicken Wire Bins';

update equipment_needed
set  `catalog_id` = (select `id` from equipment_catalog where item_name = '5 gallon buckets')
where item_name = '5 gallon buckets';

update equipment_needed
set  `catalog_id` = (select `id` from equipment_catalog where item_name = 'Spray Paint')
where item_name = 'Spray Paint';

update equipment_needed
set  `catalog_id` = (select `id` from equipment_catalog where item_name = 'Open Sign')
where item_name = 'Open Sign';

update equipment_needed
set  `catalog_id` = (select `id` from equipment_catalog where item_name = 'Pricing Sign')
where item_name = 'Pricing Sign';

update equipment_needed
set  `catalog_id` = (select `id` from equipment_catalog where item_name = 'Calrecycle Sign')
where item_name = 'Calrecycle Sign';

update equipment_needed
set  `catalog_id` = (select `id` from equipment_catalog where item_name = 'Water Dispenser')
where item_name = 'Water Dispenser';

update equipment_needed
set  `catalog_id` = (select `id` from equipment_catalog where item_name = 'Water Bottles')
where item_name = 'Water Bottles';

update equipment_needed
set  `catalog_id` = (select `id` from equipment_catalog where item_name = 'Safe')
where item_name = 'Safe';

update equipment_needed
set  `catalog_id` = (select `id` from equipment_catalog where item_name = 'Security System')
where item_name = 'Security System';

update equipment_needed
set  `catalog_id` = (select `id` from equipment_catalog where item_name = 'Hand Sanitizer')
where item_name = 'Hand Sanitizer';

update equipment_needed
set  `catalog_id` = (select `id` from equipment_catalog where item_name = 'Working Gloves')
where item_name = 'Working Gloves';

update equipment_needed
set  `catalog_id` = (select `id` from equipment_catalog where item_name = 'Cleaning Gloves')
where item_name = 'Cleaning Gloves';

update equipment_needed
set  `catalog_id` = (select `id` from equipment_catalog where item_name = 'Ear Plugs')
where item_name = 'Ear Plugs';

update equipment_needed
set  `catalog_id` = (select `id` from equipment_catalog where item_name = 'Safety Goggles')
where item_name = 'Safety Goggles';

update equipment_needed
set  `catalog_id` = (select `id` from equipment_catalog where item_name = 'Office Desk')
where item_name = 'Office Desk';

update equipment_needed
set  `catalog_id` = (select `id` from equipment_catalog where item_name = 'Change/Cash Deposit Bags')
where item_name = 'Change/Cash Deposit Bags';

update equipment_needed
set  `catalog_id` = (select `id` from equipment_catalog where item_name = 'Laptop')
where item_name = 'Laptop';

update equipment_needed
set  `catalog_id` = (select `id` from equipment_catalog where item_name = 'Writing Pens')
where item_name = 'Writing Pens'

;

Answer 1

尝试这样的事情：

update equipment_needed as t1
set  `catalog_id` = (select `id`
    from equipment_catalog as t2
    where t2.item_name = t1.item_name)

Answer 2

这似乎不是SQL Server的问题，但我认为它在MySQL中也是如此：

update equipment_needed
set  `catalog_id` = (select `id` from equipment_catalog 
where item_name = equipment_needed.item_name)

如果您需要限制提取的名称，最后可以添加更多条件，如下所示：

...
where item_name = equipment_needed.item_name)
item_name in ('Calrecycle Sign', 'Water Dispenser', ...);

Answer 3

更新equipment_needed为t1 set item_name =（select item_name 从equipment_catalog为t2 WHERE22.id = t1.needed_id） ; 更新equipment_needed为t1 set quantity_type =（选择quantity_type 从equipment_catalog为t2 WHERE22.id = t1.needed_id） ; 更新equipment_needed为t1 设置category =（选择category 来自equipment_catalog为t2 其中t2.id = t1.needed_id） ; #run for equipment_needed

将equipment_owned更新为t1 set item_name =（select item_name 从equipment_catalog为t2 WHERE t2.id = t1.owned_id） ; 将equipment_owned更新为t1 set quantity_type =（选择quantity_type 从equipment_catalog为t2 WHERE t2.id = t1.owned_id） ; 将equipment_owned更新为t1 设置category =（选择category 来自equipment_catalog为t2 其中t2.id = t1.owned_id） ; #run for equipment_owned

翻转它以使用ID进行验证而不是名称，因为它更简单。

如何减少查询次数

3 个答案: