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CREATE TABLE t(
provenance_country VARCHAR(100),
provenance_locality VARCHAR(100),
provenance_place VARCHAR(100)
)
INSERT INTO t VALUES
('Unknown', 'Unknown', 'Unknown'),
('Known1', 'Unknown', 'Known3');
SELECT
IFNULL(CONCAT_WS(', ',
IF(provenance_country = 'Unknown' OR provenance_country = 'Not Applicable', NULL, provenance_country),
IF(provenance_locality = 'Unknown' OR provenance_locality = 'Not Applicable', NULL, provenance_locality),
IF(provenance_place = 'Unknown' OR provenance_place = 'Not Applicable', NULL, provenance_place)
), '-') AS provenance_loc
FROM t;
| provenance_loc |
|---|
| Known1, Known3 |
SELECT
IFNULL(NULLIF(CONCAT_WS(', ',
IF(provenance_country = 'Unknown' OR provenance_country = 'Not Applicable', NULL, provenance_country),
IF(provenance_locality = 'Unknown' OR provenance_locality = 'Not Applicable', NULL, provenance_locality),
IF(provenance_place = 'Unknown' OR provenance_place = 'Not Applicable', NULL, provenance_place)
), ''), '-') AS provenance_loc
FROM t;
| provenance_loc |
|---|
| - |
| Known1, Known3 |