FirstLexicalToken returns the first lexical token.

HasMultipleStatements returns true if the sql string contains more than one statements.

LastLexicalToken returns the last lexical token.

NewNumValFn allows us to use tree.NewNumVal without a dependency on tree.

NewPlaceholderFn allows us to use tree.NewPlaceholder without a dependency on tree.

Scanner lexes SQL statements.

ScanSymType is the interface for accessing the fields of a yacc symType.