Points to remember: Map doesn't allow duplicate keys, but it allows duplicate values. HashMap and LinkedHashMap allows null keys and null values but TreeMap
Can I have a primary key as a non-unique column Can I pass parameter to an ALTER DATABASE command Can I prevent deadlock during concurrent delete Can I print to file using T- SQL Can I sort an SQL table? Can I sort row without order by clause Can I UPDATE, then INSERT if no rec...
SQL Server Development (2000) Can't insert NULL into table with unique key
ALTER TABLE dbo.test1 ALTER COLUMN col1 int NOT NULL; PRINT 'Executing'; INSERT dbo.test1 VALUES (NULL); GO DROP TABLE dbo.test1; GO -- Compile time error CREATE TABLE test1 (col1 int NULL); GO ALTER TABLE test1 ALTER COLUMN col1 int NOT NULL; ALTER TABLE test1 ADD ...
CREATETABLEmy_table( idINTUNSIGNEDNOT NULLAUTO_INCREMENT, nameVARCHAR(100)NOT NULL,PRIMARY KEY(id) ) AUTO_INCREMENT=10000; The issue I need to create a table with bigint primary key starting at 10000. Generated script CREATE TABLE`Identity.User`(`Id`bigintNOT NULLAUTO_INCREMENT,`UniqueId`va...
Hello All,I've never had this issue but for some reason it's become a problem.I sent out he annual Christmas get together invite in Outlook as a...
Check if linq result is null. check if the data column and the data row have the same value in a datatable check if the datarow has values in datatable check if the result is integer or not check if variable is number in C# Check if vb.net string contains any letters or numbers Ch...
I am running Windows admin center version 1910. I am finding that i can't use powershell or console to windows containers. I get this error: Using the most current version of Chrome as a browser. Any ideas? Thank You.
jfinal更新信息的时候,返回错误: com.jfinal.plugin.activerecord.ActiveRecordException: You can't update model without Primary Key, id can not be null. 解决: 查看自己设置的ID,是不是与数据库中表的ID一致,注意大小写。
NULL, PRIMARY KEY (`id`) ) ENGINE=InnoDB AUTO_INCREMENT=15 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci; insert test(name) values('12312312'); insert test(name) values('12312312'); insert test(name) values('12312312'); insert test(name) values('12312312'); insert test(name) ...