unique-key

相关标签：javascript jquery android 多少钱 iPhone

Colorize Unique Elements in XML using XSLT

I currently have an XML document which basically consists of several conversations between people just like an IM conversation.[详细]

2023-01-03 12:06 分类：问答
How Can I assign a sequence value to a sqlite field when the field UID value is NULL

How I can assign a sequence value to a field \"UID\" which is NUll in existing sqlite table, for example[详细]

2023-01-03 10:02 分类：问答
Multiple keys/indeces/constraints when joining three tables

I\'m getting more and more confused as I try to distinguish from the ambiguities of these terms.I have a query that is taking longer than necessary simply because I cannot get the key on on table to w[详细]

2023-01-03 02:04 分类：问答
What is the difference b/w Primary Key and Unique Key

I tried to find it out in google but not satisfactory answer is given out there. Can anyb开发者_运维技巧ody explain the solid difference.[详细]

2023-01-02 01:20 分类：问答
How do I create an index on a table that is non unique?

I want an index on a non-primary key column, but this column may have nulls in it. I find on a normal unique index, it (rightly 开发者_Python百科so) only allows one null.[详细]

2023-01-01 03:13 分类：问答
Unique keys in Entity Framework 4

An existing DB schema has uniqu开发者_运维技巧e, non-primary, keys, and some foreign keys that rely on them.[详细]

2022-12-26 03:17 分类：问答
How to enforce unique-field validation in MVC

I am in the way building some MVC Application and I really love the Data Annotations support in MVC. The build in support is good enough to enforce simple validation checkup. I wonder, how to implemen[详细]

2022-12-25 18:29 分类：问答
Fastest way to compute a "Visual" checksum of an image

I\'m looking to create an ID system for cataloging images.I can\'t use md5() since that will change if I a开发者_开发问答lter the EXIF tags of the image.[详细]

2022-12-24 08:22 分类：问答
Change from "unqiue=True" to "unique=False" in django

I have a model with a CharField that earlier had \"unique\" set to True, but wich now is changed to False. But when i try to save that 开发者_运维问答field with something that exists django still thro[详细]

2022-12-16 10:13 分类：问答
mysql doesn't take accents into account validating uniqueness of index key

I have a table with just a single field named \"tag\", which is a varchar(250) the field is defined with collation \'latin1_spanish_ci\', because I\'m planning to save words in spanish...[详细]

2022-12-15 18:48 分类：问答