Convert SQL Server update set from (with a join) to Oracle - oracle

Question

SQL Server table definition:
CREATE TABLE #tmp_pricing
(
contract_nbr integer not null,
pricing_order integer not null,
priced_from_contract_flag char(1) COLLATE DATABASE_DEFAULT not null,
release_nbr integer null,
quantity decimal(25, 6) not null,
price decimal(25, 6) null,
price_future decimal(25, 6) null,
price_basis decimal(25, 6) null,
sum_qty decimal(25, 6) null,
row_nbr integer null,
new_quantity decimal(25, 6) null
)
Oracle global temporary table definition
CREATE GLOBAL TEMPORARY TABLE gtt_cpr_tmp_pricing
(
contract_nbr number not null,
pricing_order number not null,
priced_from_contract_flag char(1) not null,
release_nbr number not null,
quantity number(25,6) not null,
price number(18,6) null,
price_future number(18,6) null,
price_basis number(18,6) null,
sum_qty number(25,6) null,
row_nbr number null,
new_quantity number(25,6) null
)
ON COMMIT DELETE ROWS
tablespace temp
/
SQL Server SQL statement:
UPDATE #tmp_pricing
SET row_nbr = Q.row_nbr
FROM #tmp_pricing
JOIN (SELECT contract_nbr,
pricing_order,
priced_from_contract_flag,
release_nbr,
ROW_NUMBER() OVER (PARTITION BY contract_nbr
ORDER BY contract_nbr,
priced_from_contract_flag,
CASE WHEN pricing_order < 0
THEN 1
ELSE 0
END,
pricing_order
) AS row_nbr
FROM #tmp_pricing
) Q
ON #tmp_pricing.contract_nbr = Q.contract_nbr
AND #tmp_pricing.pricing_order = Q.pricing_order
AND #tmp_pricing.priced_from_contract_flag = Q.priced_from_contract_flag
AND COALESCE(#tmp_pricing.release_nbr, 0) = COALESCE(Q.release_nbr, 0)
Oracle statement (using Merge)
MERGE INTO gtt_cpr_tmp_pricing t
USING (SELECT contract_nbr,
pricing_order,
priced_from_contract_flag,
release_nbr,
ROW_NUMBER() OVER (PARTITION BY contract_nbr
ORDER BY contract_nbr,
priced_from_contract_flag,
CASE WHEN pricing_order < 0
THEN 1
ELSE 0
END,
pricing_order
) AS row_nbr
FROM gtt_cpr_tmp_pricing
)
Q
ON (t.contract_nbr = Q.contract_nbr AND
t.pricing_order = Q.pricing_order AND
t.priced_from_contract_flag = Q.priced_from_contract_flag AND
COALESCE(t.release_nbr, 0) = COALESCE(Q.release_nbr, 0)
)
WHEN MATCHED
THEN UPDATE SET row_nbr = Q.row_nbr;
This is the error I get:
ORA-30926: unable to get a stable set of rows in the source tables
I would like to convert the statement to an update .. set ..where exists
structure but am doing something wrong; here is my (first) attempt:
UPDATE gtt_cpr_tmp_pricing
SET row_nbr = (SELECT contract_nbr,
pricing_order,
priced_from_contract_flag,
release_nbr,
ROW_NUMBER() OVER (PARTITION BY contract_nbr
ORDER BY contract_nbr,
priced_from_contract_flag,
CASE WHEN pricing_order < 0
THEN 1
ELSE 0
END,
pricing_order
) AS row_nbr
FROM gtt_cpr_tmp_pricing ctp
WHERE gtt_cpr_tmp_pricing.contract_nbr = contract_nbr
AND gtt_cpr_tmp_pricing.pricing_order = pricing_order
AND gtt_cpr_tmp_pricing.priced_from_contract_flag = priced_from_contract_flag
AND COALESCE(gtt_cpr_tmp_pricing.release_nbr, 0) = COALESCE(release_nbr, 0)
)
WHERE EXISTS (SELECT 1
FROM gtt_cpr_tmp_pricing
WHERE gtt_cpr_tmp_pricing.contract_nbr = contract_nbr
AND gtt_cpr_tmp_pricing.pricing_order = pricing_order
AND gtt_cpr_tmp_pricing.priced_from_contract_flag = priced_from_contract_flag
AND COALESCE(gtt_cpr_tmp_pricing.release_nbr, 0) = COALESCE(release_nbr, 0)
);
Any assistance would be appreciated.
Murray

Answer 1

When you use inline views in Oracle, columns without an alias reference the tables in the inline view. You need to use a table alias to reference the table in the update clause inside your inline views. Note the price_outer alias and where it's used.
UPDATE gtt_cpr_tmp_pricing price_outer
SET row_nbr = (SELECT contract_nbr,
pricing_order,
priced_from_contract_flag,
release_nbr,
ROW_NUMBER() OVER (PARTITION BY contract_nbr
ORDER BY contract_nbr,
priced_from_contract_flag,
CASE WHEN pricing_order < 0
THEN 1
ELSE 0
END,
pricing_order
) AS row_nbr
FROM gtt_cpr_tmp_pricing ctp
WHERE price_outer.contract_nbr = contract_nbr
AND price_outer.pricing_order = pricing_order
AND price_outer.priced_from_contract_flag = priced_from_contract_flag
AND COALESCE(price_outer.release_nbr, 0) = COALESCE(release_nbr, 0)
)
WHERE EXISTS (SELECT 1
FROM gtt_cpr_tmp_pricing
WHERE price_outer.contract_nbr = contract_nbr
AND price_outer.pricing_order = pricing_order
AND price_outer.priced_from_contract_flag = priced_from_contract_flag
AND COALESCE(price_outer.release_nbr, 0) = COALESCE(release_nbr, 0)
);