Internal Operations

This section describes the underlying steps that Sybase IQ performs on remote servers on behalf of client applications.

• Query Parsing
  When a statement is received from a client, the database server parses it. The database server raises an error if the statement is not a valid SQL Anywhere SQL statement.
• Query Normalization
  In query normalization, referenced objects are verified and data type compatibility is checked.
• Query Preprocessing
  Query preprocessing prepares the query for optimization.
• Server Capabilities
  Each remote server defined to Sybase IQ has a set of capabilities associated with it. These capabilities are stored in the syscapabilities system table.
• Complete Passthrough of the Statement
  The most efficient way to handle a statement is usually to pass as much of the original statement as possible to the remote server involved.
• Partial Passthrough of the Statement
  If a statement contains references to multiple servers, or uses SQL features not supported by a remote server, the query is decomposed into simpler parts.