Hello,

I have download firebirdsql from CVS and rebuild.
The results of DatabaseMetaData and ResultSetMetaData have been patched.
But I think that there are still some errors.
I have some questions want to clarify.

Take the sample I used last time
(the VARCHAR(10) column is CHARSET UNICODE_FSS)

Database MetaData

type COLUMN_SIZE DECIMAL_DIGITS

VARCHAR(10) 30 0
INTEGER 10 0
DECIMAL(11,2) 11 2
DECIMAL(5,4) 5 4
DATE 10 0
TIME 8 0
TIMESTAMP 19 0

ResultSet MetaData

type getColumnDisplaySize getPrecision getScale

VARCHAR(10) 30 30 0
INTEGER 11 10 0
DECIMAL(11,2) 8 8 2
DECIMAL(5,4) 4 4 4
DATE 10 10 0
TIME 8 8 0
TIMESTAMP 19 19 0

I have try using NUMERIC instead of DECIMAL, but it returns the same
result.

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The following is extracted from
http://java.sun.com/j2se/1.4/docs/api/java/sql/DatabaseMetaData.html#getColumns(java.lang.String,%20java.lang.String,%20java.lang.String,%20java.lang.String)

7. COLUMN_SIZE int => column size. For char or date types this is the
maximum number of characters, for numeric or decimal types this is
precision.
8. BUFFER_LENGTH is not used.
9. DECIMAL_DIGITS int => the number of fractional digits

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The following is extracted from API documentation for ResultSetMetaData

getColumnDisplaySize
--------------------
public int getColumnDisplaySize(int column)
throws SQLException

Indicates the designated column's normal maximum width in characters.

Parameters:
column - the first column is 1, the second is 2, ...
Returns:
the normal maximum number of characters allowed as the width
of the designated column
Throws:
SQLException - if a database access error occurs

getPrecision
------------
public int getPrecision(int column)
throws SQLException

Get the designated column's number of decimal digits.

Parameters:
column - the first column is 1, the second is 2, ...
Returns:
precision
Throws:
SQLException - if a database access error occurs

------

The following is extracted from
http://www.ibphoenix.com/ibp_data_types.html

To summarise the manual:

* Precision means the total number of digits stored - inclusive of
both sides of the decimal point.
* Scale is the number of those digits that are to the right of the
decimal point.
* Numeric means that the largest value stored is dictated by
(precision-scale).
* Decimal means that numbers with larger than precision-scale will
be stored; decimal specifies at least in contrast to numerics' the most.

------

The following is extracted from
http://www.ibphoenix.com/netfradb/search.nfs?a=knowledgebase&l=;KNOWLEDGEBASE.PAGES;ID=%27482%27

Once you use precision 10 or greater, InterBase internally stores the
value as a 64-bit IEEE double float.
If you use precision 9 or less, InterBase uses 16-bit or 32-bit
integer type with a scale value to store the number, ......

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(1) VARCHAR(10) CHARSET UNICODE_FSS
* According to the API documentation, the COLUMN_SIZE of
DatabaseMetaData should return maximum number of charcters for char (&
varchar)
But interclient and firebirdsql returns 30. I think it should
return 10.
I have tested with DB2 and Oracle, they do return 10.
Please note that 30 is the maximum number of BYTES for a maximum
of 10 UTF8 CHARACTERS.
* According to API doc, ResultSetMetaData.getColumnDisplaySize()
should be maximum width characters, and thus 10 in the sample, but
when count display size, ...
* ResultSetMetaData.getPrecision() - for char or varchar, I think
precision is also the maximum number of characters.
So it should return 10.
I have tested with DB2 and Oracle, they do return 10.

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(2) NUMERIC(11,2)
* DatabaseMeta COLUMN_SIZE return 11. It is OK.
* The API doc for ResultSetMetaData.getPrecision() returns precision,
so it should be 11.
But firebirdsql returns 8. As it is stored in IEEE double, 8 is
the internal buffer size in BYTES but not the precision.
* The maximum format for NUMERIC(11,2) as displayed is -999999999.99
(without thousands separator).
So ResultSetMetaData.getColumnDisplaySize() should return 13. But
firebirdsql returns 8.

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(3) NUMERIC(5,4)
* DatabaseMeta COLUMN_SIZE return 5. It is OK.
* The API doc for ResultSetMetaData.getPrecision() returns precision,
so it should be 5.
But firebirdsql returns 4. As it is stored in 16-bit or 32-bit
integer, 4 is the internal buffer size in BYTES but not the precision.
* The maximum format for NUMERIC(5,4) as displayed is -9.9999
(without thousands separator).
So ResultSetMetaData.getColumnDisplaySize() should return 7. But
firebirdsql returns 4.

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Please check and a patch is appreciated.

Thanks
CN