SnowConvert: Oracle Pseudocolumns¶

ROWID¶

Description¶

For each row in the database, the ROWID pseudocolumn returns the address of the row. (Oracle SQL Language Reference Rowid pseudocolumn)

Snowflake does not have an equivalent for ROWID. The pseudocolumn is transformed to NULL in order to avoid runtime errors.

ROWID
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Sample Source Patterns¶

Oracle¶

 CREATE TABLE sample_table
(
    sample_column varchar(10)
);

INSERT INTO sample_table(sample_column) VALUES ('text 1');
INSERT INTO sample_table(sample_column) VALUES ('text 2');

SELECT ROWID FROM sample_table;
SELECT MAX(ROWID) FROM sample_table;
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|ROWID             |
|------------------|
|AAASfCAABAAAIcpAAA|
|AAASfCAABAAAIcpAAB|
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|MAX(ROWID)        |
|------------------|
|AAASfCAABAAAIcpAAB|
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Snowflake¶
 CREATE OR REPLACE TABLE sample_table
    (
        sample_column varchar(10)
    )
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},"attributes":{"component":"oracle"}}'
;

INSERT INTO sample_table(sample_column) VALUES ('text 1');

INSERT INTO sample_table(sample_column) VALUES ('text 2');

SELECT
--** SSC-FDM-OR0030 - ROWID PSEUDOCOLUMN IS NOT SUPPORTED IN SNOWFLAKE, IT WAS CONVERTED TO NULL TO AVOID RUNTIME ERRORS **
'' AS ROWID
FROM
sample_table;

SELECT MAX(
--** SSC-FDM-OR0030 - ROWID PSEUDOCOLUMN IS NOT SUPPORTED IN SNOWFLAKE, IT WAS CONVERTED TO NULL TO AVOID RUNTIME ERRORS **
'' AS ROWID) FROM
sample_table;
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|NULL|
|----|
|    |
|    |
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|MAX(/*** MSC-ERROR - MSCEWI3094 - ROWID PSEUDOCOLUMN IS NOT SUPPORTED IN SNOWFLAKE, IT WAS CONVERTED TO NULL TO AVOID RUNTIME ERRORS ***/
NULL)|
|------------------------------------------------------------------------------------------------------------------------------------------------|
|                                                                                                                                                |
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Known Issues¶

No issues were found.

ROWNUM¶

Description¶

For each row returned by a query, the ROWNUM pseudocolumn returns a number indicating the order in which Oracle selects the row from a table or set of joined rows. (Oracle SQL Language Reference Rownum pseudocolumn)

Snowflake does not have an equivalent for ROWNUM. The approach for the transformation is taking advantage of the Snowflake seq8 function to emulate the functionality.

ROWNUM
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Sample Source Patterns¶

Oracle¶

-- Table with sample data
CREATE TABLE TABLE1(COL1 VARCHAR(20), COL2 NUMBER);
INSERT INTO TABLE1 (COL1, COL2) VALUES('ROWNUM: ', null);
INSERT INTO TABLE1 (COL1, COL2) VALUES('ROWNUM: ', null);

-- Query 1: ROWNUM in a select
SELECT ROWNUM FROM TABLE1;

-- Query 2: ROWNUM in DML
UPDATE TABLE1 SET COL2 = ROWNUM;
SELECT * FROM TABLE1;
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|ROWNUM|
|------|
|1     |
|2     |
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|COL1    |COL2|
|--------|----|
|ROWNUM: |1   |
|ROWNUM: |2   |
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Snowflake¶
 -- Table with sample data
CREATE OR REPLACE TABLE TABLE1 (COL1 VARCHAR(20),
COL2 NUMBER(38, 18) /*** SSC-FDM-0006 - NUMBER TYPE COLUMN MAY NOT BEHAVE SIMILARLY IN SNOWFLAKE. ***/
)
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},{"attributes":{"component":"oracle"}}'
;

INSERT INTO TABLE1(COL1, COL2) VALUES('ROWNUM: ', null);

INSERT INTO TABLE1(COL1, COL2) VALUES('ROWNUM: ', null);

-- Query 1: ROWNUM in a select
SELECT
seq8() + 1
FROM
TABLE1;

-- Query 2: ROWNUM in DML
UPDATE TABLE1
SET COL2 = seq8() + 1;

SELECT * FROM
TABLE1;
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|SEQ8() + 1|
|----------|
|1         |
|2         |
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|COL1    |COL2|
|--------|----|
|ROWNUM: |1   |
|ROWNUM: |2   |
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Known Issues¶

No issues were found.

Related EWIs¶

  1. SSC-FDM-0006: Number type column may not behave similarly in Snowflake

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