Class DBI::SQL::PreparedStatement
In: lib/dbi/sql/preparedstatement.rb
Parent: Object

The PreparedStatement class attempts to provide binding functionality for database systems that do not have this built-in. This package emulates the whole concept of a statement.

Methods

bind   new   tokens   tokens  

Attributes

unbound  [RW] 

Public Class methods

"prepare" a statement.

quoter is deprecated and will eventually disappear, it is kept currently for compatibility. It is safe to pass nil to this parameter.

sql is the statement itself.

[Source]

# File lib/dbi/sql/preparedstatement.rb, line 25
            def initialize(quoter, sql)
                @quoter, @sql = quoter, sql
                prepare
            end

Convenience method for consumers that just need the tokens method.

[Source]

# File lib/dbi/sql/preparedstatement.rb, line 13
            def self.tokens(sql)
                self.new(nil, sql).tokens
            end

Public Instance methods

attempts to bind the arguments in args to this statement. Will raise StandardError if there are any extents issues.

[Source]

# File lib/dbi/sql/preparedstatement.rb, line 62
            def bind(args)
                if @arg_index < args.size
                    raise "Too many SQL parameters"
                elsif @arg_index > args.size
                    raise "Not enough SQL parameters"
                end

                @unbound.each do |res_pos, arg_pos|
                    @result[res_pos] = args[arg_pos]
                end

                @result.join("")
            end

Break the sql string into parts.

This is NOT a full lexer for SQL. It just breaks up the SQL string enough so that question marks, double question marks and quoted strings are separated. This is used when binding arguments to "?" in the SQL string.

C-style (/* */) and Ada-style (—) comments are handled.

Note:Nested C-style comments are NOT handled!

[Source]

# File lib/dbi/sql/preparedstatement.rb, line 40
            def tokens
                @sql.scan(%r{
                    (
                        -- .*                               (?# matches "--" style comments to the end of line or string )
                        |   -                                   (?# matches single "-" )
                        |
                        /[*] .*? [*]/                       (?# matches C-style comments )
                        |   /                                   (?# matches single slash )    
                        |
                        ' ( [^'\\]  |  ''  |  \\. )* '  (?# match strings surrounded by apostophes )
                        |
                        " ( [^"\\]  |  ""  |  \\. )* "      (?# match strings surrounded by " )
                        |
                        \?\??                               (?# match one or two question marks )
                        |
                        [^-/'"?]+                           (?# match all characters except ' " ? - and / )

                )}x).collect {|t| t.first}
            end

[Validate]