Wolfgang Riedmann Blog

Trying to optimize building SQL insert and update strings, the following VO code:

cTable + ‘”‘ + cFieldName + ‘”‘

in Vulcan.NET works as follows

cTable + “.” + chr( 34 ) + cFieldName + chr( 34 )

But of course is not very performant. Better is the following code:

string.Format( e”{0}.\”{1}\””, cTable, aValues[nI,1] )

Please note the “e” character before the string – it enables escaping the double quotes with the backslash.

The entire method for building an append statement ist the following:

static method CreateInsertString( cTable as string, oFieldValues as List<BaseField> ) as string
 local oField as BaseField
 local oStatement as StringBuilder
 local oValues as StringBuilder
 local cStatement as string
 local cValues as string
 local nLen as int
 local nI as int
 local cField as string
 local uValue as usual
 local cValue as string

 cStatement := string.Format( “insert into {0} ( “, cTable )
 oStatement := StringBuilder{ cStatement, 512 }
 oStatement:Append( ” values ( ” )
 oValues := StringBuilder{ 512 }
 nLen := oFieldValues:Count – 1
  for nI := 0 upto nLen
  oField := oFieldValues:Item[nI]
  cValue := FirebirdHelper.ConvertValueToStatement( oField:Value )
  if nI < nLen
   oStatement:AppendFormat( “{0}, “, oField:Name )
   oValues:AppendFormat( “{0}, “, cValue )
  else
   oStatement:AppendFormat( “{0}) “, oField:Name )
   oValues:AppendFormat( “{0}) “, cValue )
  endif
 next
 oStatement:Append( oValues )
 cStatement := oStatement:ToString()

 return cStatement