procedure B_IMP_I_REESTR ( 
    IDUSER integer, 
    IMPMODE integer, 
    IDGEN integer, 
    IDPARENT integer, 
    IDTCH integer, 
    NOMER varchar(15), 
    SBORNIK integer, 
    NAME varchar(250), 
    VIX_DAN blob sub_type 0 segment size 80, 
    ISSYSTEM integer, 
    POKAZ varchar(8), 
    GOD integer, 
    RABMAT integer, 
    IDGROUP integer, 
    IDPODGROUP integer, 
    IDTYPE integer, 
    ORDERVIEW integer, 
    CREATEDATE date, 
    AUTHOR varchar(250), 
    NORM_GUID varchar(100), 
    INSTALL_GUID varchar(100), 
    INDEX_YEAR integer, 
    INDEX_MONTH integer, 
    INDEX_ORGNAME varchar(250), 
    INDTYPE varchar(50)) 
returns ( 
    ID integer) 

SELECT 1 AS "C1", "A"."ID" AS "ID" 
FROM "B_IMP_I_REESTR"(CAST(@IDUSER AS INT), CAST(@IMPMODE AS INT), CAST(@IDGEN AS INT), 
CAST(@IDPARENT AS INT), CAST(@IDTCH AS INT), CAST(@NOMER AS VARCHAR(8191)), 
CAST(@SBORNIK AS INT), CAST(@NAME AS VARCHAR(8191)), CAST(@VIX_DAN AS BLOB SUB_TYPE BINARY), 
CAST(@ISSYSTEM AS INT), CAST(@POKAZ AS VARCHAR(8191)), CAST(@GOD AS INT), 
CAST(@RABMAT AS INT), CAST(@IDGROUP AS INT), CAST(@IDPODGROUP AS INT), 
CAST(@IDTYPE AS INT), CAST(@ORDERVIEW AS INT), CAST(@CREATEDATE AS TIMESTAMP), 
CAST(@AUTHOR AS VARCHAR(8191)), CAST(@NORM_GUID AS VARCHAR(8191)), CAST(@INSTALL_GUID AS VARCHAR(8191)), 
CAST(@INDEX_YEAR AS INT), CAST(@INDEX_MONTH AS INT), CAST(@INDEX_ORGNAME AS VARCHAR(8191)), 
CAST(@INDTYPE AS VARCHAR(8191))) 
AS "A" 

var Context = new DbEntities();
var temp_B_IMP_I_REESTR = Context.B_IMP_I_REESTR
(
 10, 1, 19105302, 
 1399455, null, "132456", 
 0, "some text", null, 
 0, "", null, 0,
 1, 1, 1399451, 
 6000000, null, "some other text",
 Guid.NewGuid().ToString(), null, null, 
 null, "", "some random text"
);
foreach (B_IMP_I_REESTR_ReturnType bImpReestReturnComplexType in temp_B_IMP_I_REESTR)
{
 MessageBox.Show(bImpReestReturnComplexType.ID.ToString());
}

SELECT * FROM B_IMP_I_REESTR(CAST(@IDUSER AS INT), CAST(@IMPMODE AS INT),
CAST(@IDGEN AS INT), CAST(@IDPARENT AS INT), CAST(@IDTCH AS INT),
CAST(@NOMER AS VARCHAR(8191)), CAST(@SBORNIK AS INT),
CAST(@NAME AS VARCHAR(8191)), CAST(@VIX_DAN AS BLOB SUB_TYPE BINARY),
CAST(@ISSYSTEM AS INT), CAST(@POKAZ AS VARCHAR(8191)), CAST(@GOD AS INT),
CAST(@RABMAT AS INT), CAST(@IDGROUP AS INT), CAST(@IDPODGROUP AS INT),
CAST(@IDTYPE AS INT), CAST(@ORDERVIEW AS INT), CAST(@CREATEDATE AS TIMESTAMP),
CAST(@AUTHOR AS VARCHAR(8191)), CAST(@NORM_GUID AS VARCHAR(8191)),
CAST(@INSTALL_GUID AS VARCHAR(8191)), CAST(@INDEX_YEAR AS INT),
CAST(@INDEX_MONTH AS INT), CAST(@INDEX_ORGNAME AS VARCHAR(8191)),
CAST(@INDTYPE AS VARCHAR(7191)))

Undefined name.
Dynamic SQL Error.
SQL error code = -204.
Implementation limit exceeded.
block size exceeds implementation restriction.

План
PLAN (B_TEMP_BLOB INDEX (RDB$PRIMARY4))(B_TEMP_BLOB INDEX (RDB$PRIMARY4))(B_IMP_F_REESTR NATURAL)(B_REESTR INDEX (B_REESTR_PARENT))(B_READ_DEFAULT_REESTR_GROUPS NATURAL)(B_FIND_IND_PARAMS NATURAL)(B_REESTR INDEX (B_REESTR_PARENT))(B_REESTR INDEX (RDB$PRIMARY52))(B_REESTR INDEX (RDB$PRIMARY52))
Адаптированный план
PLAN (B_TEMP_BLOB INDEX (PK_B_TEMP_BLOB))(B_TEMP_BLOB INDEX (PK_B_TEMP_BLOB))(B_IMP_F_REESTR NATURAL)(B_REESTR INDEX (B_REESTR_PARENT))(B_READ_DEFAULT_REESTR_GROUPS NATURAL)(B_FIND_IND_PARAMS NATURAL)(B_REESTR INDEX (B_REESTR_PARENT))(B_REESTR INDEX (PK_B_REESTR))(B_REESTR INDEX (PK_B_REESTR))
------ Performance info ------
Prepare time = 32ms
Execute time = 31ms
Avg fetch time = 31,00 ms
Current memory = 10 182 588
Max memory = 10 701 300
Memory buffers = 2 048
Reads from disk to cache = 18
Writes from cache to disk = 0
Fetches from cache = 23

UnicodeVarcharMaxSize (FbProviderManifest.cs:52)

FirebirdSql.Data.EntityFramework6.SqlGen.cs:
public override ISqlFragment Visit(DbParameterReferenceExpression e) 
{ 
  _shouldCastParameter = false; 
  ... 
 _shouldCastParameter = true; 
  return result; 
}

SELECT 
1 AS "C1", 
"A"."ID" AS "ID"
FROM "B_IMP_I_REESTR"(@IDUSER, @IMPMODE, @IDGEN, @IDPARENT, @IDTCH, @NOMER, @SBORNIK, @NAME, @VIX_DAN, @ISSYSTEM, @POKAZ, @GOD, @RABMAT, @IDGROUP, @IDPODGROUP, @IDTYPE, @ORDERVIEW, @CREATEDATE, @AUTHOR, @NORM_GUID, @INSTALL_GUID, @INDEX_YEAR, @INDEX_MONTH, @INDEX_ORGNAME, @INDTYPE) AS "A"