Bug 665 - DataColumn Expressions functions TRIM and SUBSTRING don't support calculated functions as argument
Summary: DataColumn Expressions functions TRIM and SUBSTRING don't support calculated ...
Alias: None
Product: Class Libraries
Classification: Mono
Component: System.Data ()
Version: 2.10.x
Hardware: Macintosh Mac OS
: High critical
Target Milestone: Untriaged
Assignee: Bugzilla
Depends on:
Reported: 2011-09-07 12:45 UTC by Dominique NORMAND
Modified: 2012-01-06 14:10 UTC (History)
3 users (show)

Is this bug a regression?: ---
Last known good build:

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Description Dominique NORMAND 2011-09-07 12:45:03 UTC
The following expressions are not supported by System.Data:
SUBSTRING(ISNULL([columnName1] + ', ' + [columnName2], [columnName1]), 1, 200)
TRIM(ISNULL([columnName1] + ', ' + [columnName2], [columnName1]))

Reproducible: Always

Steps to Reproduce:
1. DataTable t = new DataTable() ;
2. DataColumn c1 = t.Columns.Add("c1");
3. DataColumn c2 = t.Columns.Add("c2");
4. c2.Expression = "TRIM(ISNULL(c1,' ')";
4. c2.Expression = "SUBSTRING(ISNULL(c1,' '), 1, 10)";
Actual Results:  
Unhandled Exception: System.Data.SyntaxErrorException: Expression
'TRIM(ISNULL(c1,''))' is invalid.
  at Mono.Data.SqlExpressions.Parser.Compile (System.String sqlExpr) [0x00041]
  at System.Data.DataColumn.set_Expression (System.String value) [0x000a2] in
  at TestExpression.MainClass.Main (System.String[] args) [0x00054] in

Expected Results:  
No Exception and the expression should work.

This is due to the definition of TRIM and SUBSTRING in

TRIM And SUBSTRING are StringFunction and accept only StringExpr as argument.
StringExpr allows only SingleColumnValue, StringLiteral or StringFunction but
NOT CalcFunction. So we can't even use CONVERT(<value>, "System.String") as
argument of those functions.
Comment 1 Miguel de Icaza [MSFT] 2011-09-09 22:09:14 UTC
Fixed in mono/master and mono/mono-2-10

This needs to flow to mobile-master before it gets to MonoTouch
Comment 2 PJ 2012-01-06 14:09:34 UTC
Verified as fixed in
Mono 2.10.8
MonoTouch 5.0.4
Mac 10.7.2
Comment 3 PJ 2012-01-06 14:10:12 UTC
Fix is in production. Closing.