Update 1-design-performance-migration.md

Modify the data type mapping of the number type between ORACLE and Azure Synapse

https://learn.microsoft.com/en-us/sql/relational-databases/polybase/polybase-type-mapping?view=sql-server-ver16#oracle-type-mapping-reference

Author: dialmoth

articles/synapse-analytics/migration-guides/oracle/1-design-performance-migration.md

@@ -300,7 +300,7 @@ Most Oracle data types have a direct equivalent in Azure Synapse. The following
 | LONG RAW | Not supported. Map to VARBINARY(MAX). |
 | NCHAR | NCHAR |
 | NVARCHAR2 | NVARCHAR |
-| NUMBER | NUMBER |
+| NUMBER | FLOAT |
 | NCLOB | Not directly supported. Replace with NVARCHAR(MAX). |
 | NUMERIC | NUMERIC |
 | ORD media data types | Not supported |
@@ -480,4 +480,4 @@ The [workload management guide](../../sql-data-warehouse/analyze-your-workload.m
 
 ## Next steps
 
-To learn about ETL and load for Oracle migration, see the next article in this series: [Data migration, ETL, and load for Oracle migrations](2-etl-load-migration-considerations.md).
+To learn about ETL and load for Oracle migration, see the next article in this series: [Data migration, ETL, and load for Oracle migrations](2-etl-load-migration-considerations.md).