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CREATE TABLE dossier
AS
SELECT 1 origine_client_id, 2 annee_imputation UNION ALL
SELECT NULL origine_client_id, 1 annee_imputation UNION ALL
SELECT NULL, NULL UNION ALL
SELECT 1 origine_client_id, NULL annee_imputation;
Records: 4 Duplicates: 0 Warnings: 0
SELECT COUNT(DISTINCT origine_client_id, annee_imputation) FROM dossier d1;
| COUNT(DISTINCT origine_client_id, annee_imputation) |
|---|
| 1 |
SELECT COUNT(DISTINCT d2.origine_client_id, d2.annee_imputation) FROM (SELECT origine_client_id, annee_imputation FROM dossier) as d2;
| COUNT(DISTINCT d2.origine_client_id, d2.annee_imputation) |
|---|
| 1 |
SELECT COUNT(*) FROM (SELECT DISTINCT origine_client_id, annee_imputation FROM dossier) as d3;
| COUNT(*) |
|---|
| 4 |