SELECT t.name, IDENT_CURRENT(t.name) FROM sys.tables t
WHERE IDENT_CURRENT(t.name) IS NOT NULL
ORDER BY 1

--
-- liste les colonnes IDENTITY avec leur max current value et le taux d'usage en fonction du type choisi
--
SELECT
    QUOTENAME(SCHEMA_NAME(tab.[schema_id])) + '.' +  QUOTENAME(tab.[name]) AS [TableName],
    col.[name] AS [ColumnName],
    typ.[name] AS [DataType],
    col.[last_value] AS [CurrentIdentityValue],
    col.[precision] AS [PrecisionValue],
    CAST(ROUND(CASE col.[system_type_id]
        WHEN 127 THEN (IDENT_CURRENT(SCHEMA_NAME(tab.[schema_id])  + '.' + tab.[name]) * 100.) / 9223372036854775807
        WHEN 106 THEN (IDENT_CURRENT(SCHEMA_NAME(tab.[schema_id])  + '.' + tab.[name]) * 100.) / CONVERT(NUMERIC(38,0),REPLICATE(9,col.[precision]))
        WHEN 108 THEN (IDENT_CURRENT(SCHEMA_NAME(tab.[schema_id])  + '.' + tab.[name]) * 100.) / CONVERT(NUMERIC(38,0),REPLICATE(9,col.[precision]))
        WHEN 56  THEN (IDENT_CURRENT(SCHEMA_NAME(tab.[schema_id])  + '.' + tab.[name]) * 100.) / 2147483647
        WHEN 52  THEN (IDENT_CURRENT(SCHEMA_NAME(tab.[schema_id])  + '.' + tab.[name]) * 100.) / 32767
        WHEN 48  THEN (IDENT_CURRENT(SCHEMA_NAME(tab.[schema_id])  + '.' + tab.[name]) * 100.) / 255
    END,2) as NUMERIC(4,2)) AS [PercentageUsed]
FROM
    sys.identity_columns AS col
    INNER JOIN sys.tables AS tab ON tab.[object_id] = col.[object_id]
    INNER JOIN sys.types AS typ ON col.[system_type_id] = typ.[system_type_id]
WHERE
    col.[is_identity] = 1
ORDER BY
    [PercentageUsed] DESC