Module Sequel::Dataset::PreparedStatementMethods
In: lib/sequel/dataset/prepared_statements.rb
lib/sequel/adapters/mysql.rb
lib/sequel/adapters/sqlite.rb
lib/sequel/adapters/jdbc.rb
lib/sequel/adapters/postgres.rb

Allow use of server side prepared statements for PostgreSQL using the pg driver.

Methods

call   inspect   literal_symbol   prepared_sql   run  

Included Modules

Sequel::Dataset::UnnumberedArgumentMapper BindArgumentMethods Sequel::Dataset::UnnumberedArgumentMapper BindArgumentMethods ::Sequel::Postgres::DatasetMethods::PreparedStatementMethods

Constants

PLACEHOLDER_RE = /\A\$(.*)\z/

Attributes

prepared_args  [RW]  The array/hash of bound variable placeholder names.
prepared_modify_values  [RW]  The argument to supply to insert and update, which may use placeholders specified by prepared_args
prepared_type  [RW]  The type of prepared statement, should be one of :select, :first, :insert, :update, or :delete

Public Instance methods

call(bind_vars={}, &block)

Sets the prepared_args to the given hash and runs the prepared statement.

[Source]

    # File lib/sequel/dataset/prepared_statements.rb, line 72
72:       def call(bind_vars={}, &block)
73:         bind(bind_vars).run(&block)
74:       end
inspect()

Programmer friendly string showing this is a prepared statement, with the prepared SQL it represents (which in general won‘t have substituted variables).

[Source]

     # File lib/sequel/dataset/prepared_statements.rb, line 110
110:       def inspect
111:         "<#{self.class.name}/PreparedStatement #{prepared_sql.inspect}>"
112:       end
literal_symbol(v)

Changes the values of symbols if they start with $ and prepared_args is present. If so, they are considered placeholders, and they are substituted using prepared_arg.

[Source]

     # File lib/sequel/dataset/prepared_statements.rb, line 98
 98:       def literal_symbol(v)
 99:         if @opts[:bind_vars] and match = PLACEHOLDER_RE.match(v.to_s)
100:           s = match[1].to_sym
101:           prepared_arg?(s) ? literal(prepared_arg(s)) : v
102:         else
103:           super
104:         end
105:       end
prepared_sql()

Returns the SQL for the prepared statement, depending on the type of the statement and the prepared_modify_values.

[Source]

    # File lib/sequel/dataset/prepared_statements.rb, line 78
78:       def prepared_sql
79:         case @prepared_type
80:         when :select, :all
81:           select_sql
82:         when :first
83:           clone(:limit=>1).select_sql
84:         when :insert_select
85:           clone(:returning=>nil).insert_sql(*@prepared_modify_values)
86:         when :insert
87:           insert_sql(*@prepared_modify_values)
88:         when :update
89:           update_sql(*@prepared_modify_values)
90:         when :delete
91:           delete_sql
92:         end
93:       end

Protected Instance methods

run(&block)

Run the method based on the type of prepared statement, with :select running all to get all of the rows, and the other types running the method with the same name as the type.

[Source]

     # File lib/sequel/dataset/prepared_statements.rb, line 119
119:       def run(&block)
120:         case @prepared_type
121:         when :select, :all
122:           all(&block)
123:         when :insert_select
124:           meta_def(:select_sql){prepared_sql}
125:           first
126:         when :first
127:           first
128:         when :insert
129:           insert(*@prepared_modify_values)
130:         when :update
131:           update(*@prepared_modify_values)
132:         when :delete
133:           delete
134:         end
135:       end

[Validate]