Dynamic SQL - Insert a variables via INSERT INTO x SELECT statement - sql

Question

I would like to ask how can I insert a variables into a table using INSERT INTO x SELECT statement via dynamic SQL.
I have following table:
|-------------------|-----------------|--------------|-----------------|
| TableName | ColName | Value | SQL_Statement |
|-------------------|-----------------|--------------|-----------------|
I get a content for Value column by this query:
INSERT INTO #ReturnTable(Value) SELECT TreeHolder FROM prm.Schm_Root WHERE ParentTreeHolderId = 'DD040D31-4591-4658-A02E-A6ED00AB64F2';
But I need to fill whole table. Please consider that other values are variables, not SQL queries.
SELECT #TableSchema = TableSchema FROM #TableNames WHERE Id = #Counter;
SELECT #TableName = TableName FROM #TableNames WHERE Id = #Counter;
SELECT #ColName = ColName FROM #TableNames WHERE Id = #Counter;
SET #SQL_Statement = 'SELECT ' + #ColName + ' FROM ' + #TableSchema + '.' + #TableName + ' WHERE ' + #ColName + ' = ' + '''''' + CAST(#GuidArgument AS NVARCHAR(50)) + '''''' + ';';
Now I have this query that fills a table:
SET #SQL_String = N'INSERT INTO #ReturnTable SELECT
''' + #TableName + ''',
''' + #ColName + ''',
''' + #SQL_Statement + ''',
'' + Value + '',
(SELECT ' +
#ColName + '
FROM ' +
#TableSchema + '.' + #TableName + '
WHERE ' +
#ColName + ' = ''' + CAST(#GuidArgument AS NVARCHAR(50)) + '
'')';
EXECUTE sp_executesql #SQL_String
PRINT #SQL_String;
The thing I need is to rewrite this query from INSERT INTO ? VALUE to INSERT INTO ? SELECT format.

Answer 1

If I understand correctly, you want to insert SQL execute syntax string and it results in ReturnTable table.
I would let subquery SQL execute syntax save in a variable. because the will be more clear what you need to do.
Declare a new variable #SQL_excuteStatement variable to save your execute syntax.
the #SQL_Statement to carry the original SQL string.
set #SQL_Statement = 'SELECT ' + #ColName +
' FROM ' + #TableSchema + '.' + #TableName +
' WHERE ' + #ColName + ' = '+'''''' + CAST(#GuidArgument AS NVARCHAR(50)) + '''''';
and use select ... from table instead of subquery in select
There is a sample for you.
DECLARE #SQL_String NVARCHAR(MAX)
DECLARE #TableSchema NVARCHAR(MAX)
DECLARE #TableName NVARCHAR(MAX)
DECLARE #ColName NVARCHAR(MAX)
DECLARE #Counter int = 1
DECLARE #SQL_Statement NVARCHAR(MAX)
DECLARE #GuidArgument INT = 1
CREATE TABLE TableNames(
ID INT,
TableSchema NVARCHAR(100),
TableName NVARCHAR(100),
ColName NVARCHAR(100)
);
CREATE TABLE ReturnTable(
TableName NVARCHAR(100),
ColName NVARCHAR(100),
SQL_Statement NVARCHAR(max),
value nvarchar(max)
);
INSERT INTO TableNames VALUES (1,'dbo','T','val');
CREATE TABLE T(val INT);
INSERT INTO T VALUES (1)
SELECT #TableSchema = TableSchema FROM TableNames WHERE Id = #Counter;
SELECT #TableName = TableName FROM TableNames WHERE Id = #Counter;
SELECT #ColName = ColName FROM TableNames WHERE Id = #Counter;
set #SQL_Statement = 'SELECT ' + #ColName +
' FROM ' + #TableSchema + '.' + #TableName +
' WHERE ' + #ColName + ' = '+ '''''' + CAST(#GuidArgument AS NVARCHAR(50)) + '''''';
SET #SQL_String = N'INSERT INTO ReturnTable (TableName,ColName,SQL_Statement,value)
SELECT '''+ #TableName + ''','''+ #ColName + ''','''+ #SQL_Statement + '''' + ',' + QUOTENAME(#ColName) +
' FROM ' + QUOTENAME(#TableSchema) + '.' + QUOTENAME(#TableName) + '' +
' WHERE ' + #ColName + ' = ''' + CAST(#GuidArgument AS NVARCHAR(50)) + '''';
EXECUTE sp_executesql #SQL_String
sqlfiddle
Note
I would suggest you use clear column after insert into
INSERT INTO table2 (column1, column2, column3, ...)
SELECT column1, column2, column3, ...
FROM table1
WHERE condition;