SQL Server 2016

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/****** Object:  Table [dbo].[assets]  ******/

CREATE TABLE [dbo].[assets](
	[unid] [int] NOT NULL,
	[servername] [nvarchar](50) NOT NULL
) ON [PRIMARY]

/****** Object:  Table [dbo].[managers]  ******/

CREATE TABLE [dbo].[managers](
	[unid] [nvarchar](50) NOT NULL,
	[firstname] [nvarchar](50) NULL,
	[lastname] [nvarchar](50) NULL
) ON [PRIMARY]

/****** Object:  Table [dbo].[properties] ******/

CREATE TABLE [dbo].[properties](
	[asset_id] [int] NOT NULL,
	[property] [nvarchar](50) NOT NULL,
	[property_text] [nvarchar](50) NOT NULL
) ON [PRIMARY]

INSERT [dbo].[assets] ([unid], [servername]) VALUES (1, N'saturn-n1')
INSERT [dbo].[assets] ([unid], [servername]) VALUES (2, N'saturn-n2')
INSERT [dbo].[assets] ([unid], [servername]) VALUES (3, N'mars-n1')
INSERT [dbo].[managers] ([unid], [firstname], [lastname]) VALUES (N'333-111', N'Carl', N'Cox')
INSERT [dbo].[managers] ([unid], [firstname], [lastname]) VALUES (N'333-112', N'David', N'Guetta')
INSERT [dbo].[managers] ([unid], [firstname], [lastname]) VALUES (N'333-113', N'Tim', N'Bergling')
INSERT [dbo].[properties] ([asset_id], [property], [property_text]) VALUES (1, N'manager', N'333-111')
INSERT [dbo].[properties] ([asset_id], [property], [property_text]) VALUES (1, N'stby-manager', N'333-112')
INSERT [dbo].[properties] ([asset_id], [property], [property_text]) VALUES (1, N'stage', N'Production')
INSERT [dbo].[properties] ([asset_id], [property], [property_text]) VALUES (2, N'manager', N'333-112')
INSERT [dbo].[properties] ([asset_id], [property], [property_text]) VALUES (2, N'stage', N'Production')
INSERT [dbo].[properties] ([asset_id], [property], [property_text]) VALUES (3, N'manager', N'333-113')
INSERT [dbo].[properties] ([asset_id], [property], [property_text]) VALUES (3, N'stby-manager', N'333-112')

13 rows affected

unid	servername	Manager	Stdby_Manager	Stage
1	saturn-n1	Carl	David	Production
2	saturn-n2	David	null	Production
3	mars-n1	Tim	David	null