Error creating entity Microsoft SQL server IDENTITY_INSERT - sql-server

Question

I'm using JHipster 4. I've create a simple entity just with a "name" property and when I try to create a entity from UI I get the folowing error. (I'm using Microsoft SQL Server).
In think the important part of the error is :
Caused by: com.microsoft.sqlserver.jdbc.SQLServerException: Cannot insert explicit value for identity column in table 'tenant' when IDENTITY_INSERT is set to OFF.

Answer 1

Direct answer appears to be that you just need to configure jhipster to have identity_insert on, per this link: https://jhipster.github.io/tips/004_tip_using_ms_sql_server.html
Adding the identityInsertEnabled="true" is the same as wrapping your Inserts with IDENTITY_INSERT ON and IDENTITY_INSERT OFF which will allow you to insert the project autogenerated identities directly. This is why we are using the MS SQL Server Liquibase for.
The error tells you everything you need to know. You are trying to insert a value in to an identity column. This is not allowed, as the column is supposed to be automatically populated unless you explicitly turn it off temporarily.
Documentation on what identity_insert is here: https://msdn.microsoft.com/en-us/library/ms188059.aspx
You can turn it off using the command set identity_insert SchemaName.TableName off though you had better be very confident you are inserting the correct data.
I would recommend you do some investigation with whoever manages your database as to why that column is an identity column and whether or not you should be inserting into it at all.
Assume a table:
create table test(ID int identity(1,1)
,Name nvarchar(100)
)
ALL of these insert statements will throw an error:
insert into test(ID,Name)
select ID
,Name
from OtherTable
insert into test(ID,Name)
select null as ID
,'TestName' as Name
insert into test(ID,Name)
values(99
,'Name'
)
Whereas these will work, automatically generating a new, unique value for the ID column:
insert into test(Name)
select Name
from OtherTable
insert into test(Name)
select 'TestName' as Name
insert into test(Name)
values('Name')
In short, you need to insert nothing into the identity column. Not a blank string, not a null value, but absolutely nothing at all.