Changes between Initial Version and Version 2 of Ticket #4397


Ignore:
Timestamp:
Dec 16, 2011, 9:37:09 AM (12 years ago)
Author:
esseffe
Comment:

Legend:

Unmodified
Added
Removed
Modified

  • Ticket #4397 – Description

    initial v2  
    1 I've noticed an issue in OGRFeature::GetFieldAsString()
     1Hi Even,
    22
    3 when a StringList value is exported, the following serialized notation is adopted:
    4 {{{
    5 - value#1 = "A01"
    6 - value#2 = "B02"
    7 - serialized = "(2:A01,B01)"
    8 }}}
     3so standing things there is a strong inconsistency in the SQLite [output] driver implementation.[[BR]]
    94
    10 this serialized format is generally fine (and is easily parsable by other apps), but will introduce fatal ambiguities when any COMMA is used by some value to be serialized:
    11 {{{
    12 - value#1 = "A,01"
    13 - value#2 = "B,02"
    14 - serialized = "(2:A,01,B,01)"
    15 }}}
     5I'll actually find several "serialized" values in any SpatiaLite DB created by ogr2ogr, and I'm completely unable to parse such values in a safe and consistent way. that's not all, such "serialized" values could be actually truncated, and there is no way to understand if some truncation occurred when readind the DB. Sorry, I didn't noticed this further issue. So, such "serialized" values into the DB are irremediably useless.
    166
    17 quite obviously, a serialized value like this can never be succesfully parsed so to retrieve the initial values.
     7On the other side I notice that the SHP driver completely omits to create any attribute/column of the StringList, IntegerList or RealList type: may be this one could be a better (and more consistent) design choice for the SQLite driver as well ?
    188
    19 suggested remedy: applying the same criteria used to mask quotes in SQL string, i.e. masking any COMMA found in the string value to be exported as COMMA-COMMA.
    20 This would produce the following output:
    21 {{{
    22 - value#1 = "A,01"
    23 - value#2 = "B,02"
    24 - serialized = "(2:A,,01,B,,01)"
    25 }}}
    26  
    27 a serialized string like this has no longer any ambiguity at all; and can be easily and safely parsed so to retrieve the original values.
    28 
    29 please see the attached patch
    30 
    31 best regards,
    32 Sandro Furieri
     9by Sandro