primary-key

相关标签：javascript jquery android 多少钱 iPhone

MySQL. Primary key in a relational table. Unique id or multiple unique key?

Primary key in relational tables. Composite primary key or unique primary key in those pure relational tables?[详细]

2023-03-13 15:41 分类：问答
alter table drop column syntax error using sqlite

This is the schema of my table: create table LPCG(ID integer primary key, PCG text, Desc text, test text);[详细]

2023-03-10 20:43 分类：问答
JPA primary key value is always 0

I have a post class and it kind of works, but there\'s one problem: the primary key doesn\'t increase.[详细]

2023-03-10 16:45 分类：问答
Defining primary key as virtual in Entity Framework

What\'s the benefit of defining the primary key attribute as virtual in entity Framework? AFAIK, virtual is used for lazy loading in navigation properties and for change tracking in other properties.[详细]

2023-03-10 11:43 分类：问答
choosing primary key datatype numeric (18,0)

I inherited a SQL Server database where many tables have a primary key of type numeric(18,0) . What reasons (historical perhaps?) would someone choose this datatype for 开发者_JS百科a primary key?I w[详细]

2023-03-10 10:36 分类：问答
MySQL child table need to have primary key?

I have (all InnoDB) a parenttable tbl1 with primary key some_id and child (referencing) table tbl2 with another_id referencing tbl1.some_id as foreign key. tbl2.开发者_StackOverflow社区another_id is n[详细]

2023-03-10 00:46 分类：问答
How to sort var length ids (composite string + numeric)?

I have a MySQL database whose keys are of this type: A_10 A_10A A_10B A_101 QAb801 QAc5 QAc25 QAd2993 I would like them to sort first by the alpha portion, then by the numeric portion, just like abo[详细]

2023-03-09 23:42 分类：问答
Multiple Primary Keys Table - Hibernate NonUniqueObjectException

I have a table with 2 primary keys (so the combination of both of them should be unique).The schema is like this:[详细]

2023-03-09 16:17 分类：问答
Is it possible to add a autoincrement primary index column in full mysql table belated?

Assuming this table with nearly 5 000 000 rows CREATE TABLE `author2book` ( `author_id` int(11) NOT NULL,[详细]

2023-03-09 07:50 分类：问答
django: how do i stop save(using=) from creating new primary key

In django, I want to copy data from identical tables in one db to those in another -- from \'db01\' to \'default\'. Schema are identical.[详细]

2023-03-08 15:10 分类：问答