Question

试图找出一个SQL脚本来测试cerain表中是否存在主键。如果表没有主键，则脚本应输出表名。

Tables to test:
TableA
TableB
TableC

运行脚本后（假设TableA和TableC有PK，但不是TableB），那么输出将在下面：

NoKeys
TableB

Answer 1

我没有准确/完整的代码，但这里的想法是：

您需要遍历数据库中的表列表：

SELECT *  
FROM information_schema.tables`

检查表是否存在主键的代码如下：

SELECT *  
FROM information_schema.table_constraints  
WHERE constraint_type = 'PRIMARY KEY'   
AND table_name = @Your_Table_Name`

Answer 2

;WITH tables_with_pk AS (
  SELECT t.table_schema, t.table_name  
  FROM INFORMATION_SCHEMA.TABLES t 
    INNER JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS tc 
      ON t.TABLE_NAME = tc.TABLE_NAME AND t.table_schema = tc.table_schema
  WHERE tc.constraint_type = 'PRIMARY KEY'
)
SELECT t.table_schema, t.table_name 
FROM INFORMATION_SCHEMA.TABLES t 
EXCEPT
SELECT table_schema, table_name
FROM tables_with_pk

Answer 3

我的版本：

SELECT 1  
FROM SYS.KEY_CONSTRAINTS
WHERE [TYPE] = 'PK' AND [PARENT_OBJECT_ID] = OBJECT_ID('USER.USER');

作为参考检查 Microsoft 文档 here。

Answer 4

怎么样

USE information_schema;
SELECT `TABLE_NAME` FROM `TABLES` LEFT JOIN `TABLE_CONSTRAINTS` USING(`TABLE_SCHEMA`, `TABLE_NAME`) WHERE `TABLE_SCHEMA` = '__PUT_YOUR_DB_NAME_HERE__' AND `CONSTRAINT_NAME` LIKE '%PRIMARY%' AND ISNULL(`CONSTRAINT_CATALOG`)

Answer 5

我喜欢肖恩的回答，这对我有用。您可以添加子句

WHERE t.TABLE_TYPE = 'BASE TABLE'

在EXCEPT语句之前，如果您不想再获取视图。

;WITH tables_with_pk AS (
  SELECT t.table_schema, t.table_name
  FROM INFORMATION_SCHEMA.TABLES t 
    INNER JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS tc 
      ON t.TABLE_NAME = tc.TABLE_NAME AND t.table_schema = tc.table_schema
  WHERE tc.constraint_type = 'PRIMARY KEY' 
)
SELECT t.table_schema, t.table_name
FROM INFORMATION_SCHEMA.TABLES t 
WHERE t.TABLE_TYPE = 'BASE TABLE'
EXCEPT
SELECT table_schema, table_name
FROM tables_with_pk

Answer 6

如果没有主键，则返回0，如果有主键，则返回1

implementation "androidx.core:core-ktx:1.0.1"
implementation "androidx.appcompat:appcompat:1.0.2"
implementation "androidx.activity:activity-ktx:1.0.0-alpha04"

用于测试主键是否存在的脚本

6 个答案: