Question

I have a table like this:

 - ID  | CurrencyID | LendID |  Price
 - 3   |    1       |  1      |  1.2
 - 3   |    1       |  2      |  1.3
 - 3   |    1       |  3      |  1.4
 - 3   |    2       |  1      |  1.5
 - 3   |    2       |  2      |  1.6
 - 3   |    2       |  3      |  1.7
 - 4   |    2       |  3      |  2.0

There are totally 4 currencies 1,2,3,4

There are totally 3 lend 1,2,3

I want to get a result like below:

ID | CurrencyIDLendID_11_Price | CIDID_12_Price | CIDLID_13_Price | CIDLID_21_Price | CIDLID_22_Price | CIDLID_23_Price | CIDLID_31_Price | CIDLID_32_Price | CIDLID_33_Price | CIDLID_41_Price | CIDLID_42_Price | CIDLID_43_Price
 3 | 1.2 | 1.3 | 1.4 | 1.5 | 1.6 | 1.7 | 0 | 0 | 0 | 0 | 0 | 0
 4 |  0  |  0  |  0  |  0  |  0  | 2.0 | 0 | 0 | 0 | 0 | 0 | 0

I know it is now good description, but what I want to do is to merge many records to one record.

Answer 1

This is called pivoting and one of the ways how to do the pivoting is to use grouping with conditional aggregating:

WITH cidlid AS (
  SELECT
    ID,
    CurrencyIDLendID = CurrencyID * 10 + LendID,
    Price
  FROM atable
)
SELECT
  ID,
  CurrencyIDLendID_11_Price = COALESCE(SUM(CASE CurrencyIDLendID WHEN 11 THEN Price END), 0),
  CurrencyIDLendID_12_Price = COALESCE(SUM(CASE CurrencyIDLendID WHEN 12 THEN Price END), 0),
  CurrencyIDLendID_13_Price = COALESCE(SUM(CASE CurrencyIDLendID WHEN 13 THEN Price END), 0),
  CurrencyIDLendID_21_Price = COALESCE(SUM(CASE CurrencyIDLendID WHEN 21 THEN Price END), 0),
  CurrencyIDLendID_22_Price = COALESCE(SUM(CASE CurrencyIDLendID WHEN 22 THEN Price END), 0),
  CurrencyIDLendID_23_Price = COALESCE(SUM(CASE CurrencyIDLendID WHEN 23 THEN Price END), 0),
  CurrencyIDLendID_31_Price = COALESCE(SUM(CASE CurrencyIDLendID WHEN 31 THEN Price END), 0),
  CurrencyIDLendID_32_Price = COALESCE(SUM(CASE CurrencyIDLendID WHEN 32 THEN Price END), 0),
  CurrencyIDLendID_33_Price = COALESCE(SUM(CASE CurrencyIDLendID WHEN 33 THEN Price END), 0),
  CurrencyIDLendID_41_Price = COALESCE(SUM(CASE CurrencyIDLendID WHEN 41 THEN Price END), 0),
  CurrencyIDLendID_42_Price = COALESCE(SUM(CASE CurrencyIDLendID WHEN 42 THEN Price END), 0),
  CurrencyIDLendID_43_Price = COALESCE(SUM(CASE CurrencyIDLendID WHEN 43 THEN Price END), 0)
FROM cidlid
GROUP BY ID

If all the (CurrencyID, LendID) combinations are guaranteed to be unique within same ID groups, you can also use MIN or MAX instead of SUM.