On Wednesday, 28 March 2018 00:11:29 UTC+8, Wes Clark wrote:
>
> We switched to Oracle mode so that unique indexes could allow multiple 
> null values.  Is there a way to preserve that and still use the H2 date 
> datatype?
>

In regular mode unique indexes allow multiple rows with NULL values too. 
They are forbidden only in HSQLDB, Derby, and MSSQLServer modes.

But if you use multi-column indexes there is a difference between regular 
and Oracle mode.

In Oracle mode only rows with NULL values in all indexed columns may be 
duplicated.
IDX_COL1  IDX_COL2
null      null
null      null

In regular mode rows with NULL value in any indexed column may be 
duplicated.
IDX_COL1  IDX_COL_2
null      null
null      null
null      value1
null      value2
value3    null
value4    null

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