// String and Binary handling. These are represented as a long, which is an offset into a file.
public long EncodeString( string s )
{
if ( s == "" ) return 0;
// See if it is in SysStringIndex
try
{
var start = new StringStart( s );
foreach( IndexFileRecord ixr in SysStringIndex.From( start.Compare, false ) )
{
if ( (string)(ixr.Col[0]._O) == s ) return ixr.Col[0].L;
break;
}
}
catch ( System.Exception x )
{
SysStringIndex.Dump();
throw x;
}
// Save to file.
long sid = SysString.Length;
SysString.Position = sid;
SysStringWriter.Write( s );
// Insert into the index
IndexFileRecord r = new IndexFileRecord( 1 );
r.Col[ 0 ].L = sid + 1;
r.Col[ 0 ]._O = s;
SysStringIndex.Insert( ref r );
return sid + 1; // + 1 because zero indicates the encoding has not yet been done.
}
int ReadSchemaId( string schemaName )
{
if ( schemaName == "sys" ) return 1;
var start = new StringStart( schemaName );
foreach( IndexFileRecord ixr in SysSchemaByName.From( start.Compare, false ) )
{
if ( (string)(ixr.Col[0]._O) == schemaName ) return (int)ixr.Col[1].L;
break;
}
return -1;
}
long ReadTableId( Schema schema, string name, out bool isView, out string definition )
{
var r = new RowCursor( SysTable );
var start = new StringStart( name );
foreach( IndexFileRecord ixr in SysTableByName.From( start.Compare, false ) )
{
if ( (string)(ixr.Col[0]._O) == name )
{
long id = ixr.Col[1].L;
r.Get( id );
if ( r.V[1].L == schema.Id )
{
isView = r.V[3].L != 0;
definition = (string)r.V[4]._O;
return id;
}
}
}
isView = false; definition = null;
return -1;
}