Inserting Different Value IN a Table - sql

Question

Well I'm Creating a Table Based on Result Set Of Databases On Server which contain Multiple Databases.
My table will Create a list of column which contain Database_Name
FOR EG:
DECLARE #strt INT,#End INT,#Database NVARCHAR(20), #ColumnDeclaration VARCHAR(2000),#SqlSelect NVARCHAR(MAX),#column_Name NVARCHAR(255)
SELECT * INTO #T FROM SYS.DATABASES
ORDER BY NAME
SELECT #ColumnDeclaration=STUFF(( SELECT ', ' + Name + ' NVARCHAR(255)'
FROM #T
FOR XML PATH(''), TYPE).value('.', 'NVARCHAR(max)'), 1, 1, '')
SET #SqlSelect=' CREATE TABLE Temp_Comp (' + #ColumnDeclaration + ');'
PRINT #SqlSelect
EXEC (#SqlSelect)
SELECT * FROM Temp_Comp

Answer 1

I wan't Insert the Data INTO Temp_Comp Table a specific Value from
the database whose Name will be in Temp_comp Table
Not sure what are you trying to achieve, but I assume that you want something like:
DECLARE #strt INT,#End INT,#Database NVARCHAR(20), #ColumnDeclaration NVARCHAR(MAX),#SqlSelect NVARCHAR(MAX),#column_Name NVARCHAR(255)
SELECT * INTO #T
FROM SYS.DATABASES
ORDER BY NAME;
SELECT #ColumnDeclaration=STUFF(( SELECT ', ' + QUOTENAME(Name) + ' NVARCHAR(255)'
FROM #T
FOR XML PATH(''), TYPE).value('.', 'NVARCHAR(max)'), 1, 1, '');
SET #SqlSelect=' CREATE TABLE Temp_Comp (col_desc NVARCHAR(200), ' + #ColumnDeclaration + ');';
SELECT #SqlSelect;
EXEC (#SqlSelect);
SET #SQLSelect = ' INSERT INTO Temp_Comp(col_desc, ' + REPLACE(#ColumnDeclaration, 'NVARCHAR(255)', '') + ')' +
' SELECT col,'+ REPLACE(#ColumnDeclaration, 'NVARCHAR(255)', '') +' FROM (' +
' SELECT name, sub.* FROM sys.databases' +
' OUTER APPLY (SELECT ''database_id'', CAST(database_id AS NVARCHAR(MAX)) UNION ALL SELECT ''compatibility_level'', CAST(compatibility_level AS NVARCHAR(MAX)) ) sub(col, val)) src' +
' PIVOT (MAX(val) FOR name IN ('+ REPLACE(#ColumnDeclaration, 'NVARCHAR(255)', '') +') ) piv';
SELECT #SQLSelect;
EXEC (#SQLSelect);
DBFiddle
Result:
In order to INSERT you could use dynamic PIVOT. To add more values just extend OUTER APPLY part.
Keep in mind that you've defined columns as ' NVARCHAR(255)' so you may need to convert values before insert.