Module: ActiveRecord::ConnectionAdapters::PostgreSQLAdapter::DatabaseStatements

Included in:
ActiveRecord::ConnectionAdapters::PostgreSQLAdapter
Defined in:
lib/active_record/connection_adapters/postgresql/database_statements.rb

Defined Under Namespace

Classes: ExplainPrettyPrinter

Instance Method Summary collapse

Instance Method Details

#begin_db_transaction ⇒ Object

Begins a transaction.



196
197
198
 
# File 'lib/active_record/connection_adapters/postgresql/database_statements.rb', line 196

def begin_db_transaction
  execute "BEGIN"
end

#begin_isolated_db_transaction(isolation) ⇒ Object 



200
201
202
203
 
# File 'lib/active_record/connection_adapters/postgresql/database_statements.rb', line 200

def begin_isolated_db_transaction(isolation)
  begin_db_transaction
  execute "SET TRANSACTION ISOLATION LEVEL #{transaction_isolation_levels.fetch(isolation)}"
end

#commit_db_transaction ⇒ Object

Commits a transaction.



206
207
208
 
# File 'lib/active_record/connection_adapters/postgresql/database_statements.rb', line 206

def commit_db_transaction
  execute "COMMIT"
end

#create ⇒ Object 



71
72
73
 
# File 'lib/active_record/connection_adapters/postgresql/database_statements.rb', line 71

def create
  super.insert
end

#exec_delete(sql, name = 'SQL', binds = []) ⇒ Object Also known as: exec_update 



153
154
155
156
157
158
159
 
# File 'lib/active_record/connection_adapters/postgresql/database_statements.rb', line 153

def exec_delete(sql, name = 'SQL', binds = [])
  result = without_prepared_statement?(binds) ? exec_no_cache(sql, name, binds) :
                                                exec_cache(sql, name, binds)
  affected = result.cmd_tuples
  result.clear
  affected
end

#exec_insert(sql, name, binds, pk = nil, sequence_name = nil) ⇒ Object 



176
177
178
179
180
181
182
183
184
185
186
187
188
 
# File 'lib/active_record/connection_adapters/postgresql/database_statements.rb', line 176

def exec_insert(sql, name, binds, pk = nil, sequence_name = nil)
  val = exec_query(sql, name, binds)
  if !use_insert_returning? && pk
    unless sequence_name
      table_ref = extract_table_ref_from_insert_sql(sql)
      sequence_name = default_sequence_name(table_ref, pk)
      return val unless sequence_name
    end
    last_insert_id_result(sequence_name)
  else
    val
  end
end

#exec_query(sql, name = 'SQL', binds = []) ⇒ Object 



136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
 
# File 'lib/active_record/connection_adapters/postgresql/database_statements.rb', line 136

def exec_query(sql, name = 'SQL', binds = [])
  result = without_prepared_statement?(binds) ? exec_no_cache(sql, name, binds) :
                                                exec_cache(sql, name, binds)

  types = {}
  fields = result.fields
  fields.each_with_index do |fname, i|
    ftype = result.ftype i
    fmod  = result.fmod i
    types[fname] = get_oid_type(ftype, fmod, fname)
  end

  ret = ActiveRecord::Result.new(fields, result.values, types)
  result.clear
  return ret
end

#execute(sql, name = nil) ⇒ Object

Executes an SQL statement, returning a PGresult object on success or raising a PGError exception otherwise.



126
127
128
129
130
 
# File 'lib/active_record/connection_adapters/postgresql/database_statements.rb', line 126

def execute(sql, name = nil)
  log(sql, name) do
    @connection.async_exec(sql)
  end
end

#explain(arel, binds = []) ⇒ Object 



5
6
7
8
 
# File 'lib/active_record/connection_adapters/postgresql/database_statements.rb', line 5

def explain(arel, binds = [])
  sql = "EXPLAIN #{to_sql(arel, binds)}"
  ExplainPrettyPrinter.new.pp(exec_query(sql, 'EXPLAIN', binds))
end

#insert_sql(sql, name = nil, pk = nil, id_value = nil, sequence_name = nil) ⇒ Object

Executes an INSERT query and returns the new record’s ID



54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
 
# File 'lib/active_record/connection_adapters/postgresql/database_statements.rb', line 54

def insert_sql(sql, name = nil, pk = nil, id_value = nil, sequence_name = nil)
  unless pk
    # Extract the table from the insert sql. Yuck.
    table_ref = extract_table_ref_from_insert_sql(sql)
    pk = primary_key(table_ref) if table_ref
  end

  if pk && use_insert_returning?
    select_value("#{sql} RETURNING #{quote_column_name(pk)}")
  elsif pk
    super
    last_insert_id_value(sequence_name || default_sequence_name(table_ref, pk))
  else
    super
  end
end

#query(sql, name = nil) ⇒ Object

Queries the database and returns the results in an Array-like object



118
119
120
121
122
 
# File 'lib/active_record/connection_adapters/postgresql/database_statements.rb', line 118

def query(sql, name = nil) #:nodoc:
  log(sql, name) do
    result_as_array @connection.async_exec(sql)
  end
end

#result_as_array(res) ⇒ Object

create a 2D array representing the result set



76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
 
# File 'lib/active_record/connection_adapters/postgresql/database_statements.rb', line 76

def result_as_array(res) #:nodoc:
  # check if we have any binary column and if they need escaping
  ftypes = Array.new(res.nfields) do |i|
    [i, res.ftype(i)]
  end

  rows = res.values
  return rows unless ftypes.any? { |_, x|
    x == BYTEA_COLUMN_TYPE_OID || x == MONEY_COLUMN_TYPE_OID
  }

  typehash = ftypes.group_by { |_, type| type }
  binaries = typehash[BYTEA_COLUMN_TYPE_OID] || []
  monies   = typehash[MONEY_COLUMN_TYPE_OID] || []

  rows.each do |row|
    # unescape string passed BYTEA field (OID == 17)
    binaries.each do |index, _|
      row[index] = unescape_bytea(row[index])
    end

    # If this is a money type column and there are any currency symbols,
    # then strip them off. Indeed it would be prettier to do this in
    # PostgreSQLColumn.string_to_decimal but would break form input
    # fields that call value_before_type_cast.
    monies.each do |index, _|
      data = row[index]
      # Because money output is formatted according to the locale, there are two
      # cases to consider (note the decimal separators):
      #  (1) $12,345,678.12
      #  (2) $12.345.678,12
      case data
      when /^-?\D+[\d,]+\.\d{2}$/  # (1)
        data.gsub!(/[^-\d.]/, '')
      when /^-?\D+[\d.]+,\d{2}$/  # (2)
        data.gsub!(/[^-\d,]/, '').sub!(/,/, '.')
      end
    end
  end
end

#rollback_db_transaction ⇒ Object

Aborts a transaction.



211
212
213
 
# File 'lib/active_record/connection_adapters/postgresql/database_statements.rb', line 211

def rollback_db_transaction
  execute "ROLLBACK"
end

#select_rows(sql, name = nil, binds = []) ⇒ Object

Executes a SELECT query and returns an array of rows. Each row is an array of field values.



49
50
51
 
# File 'lib/active_record/connection_adapters/postgresql/database_statements.rb', line 49

def select_rows(sql, name = nil, binds = [])
  exec_query(sql, name, binds).rows
end

#sql_for_insert(sql, pk, id_value, sequence_name, binds) ⇒ Object 



162
163
164
165
166
167
168
169
170
171
172
173
174
 
# File 'lib/active_record/connection_adapters/postgresql/database_statements.rb', line 162

def sql_for_insert(sql, pk, id_value, sequence_name, binds)
  unless pk
    # Extract the table from the insert sql. Yuck.
    table_ref = extract_table_ref_from_insert_sql(sql)
    pk = primary_key(table_ref) if table_ref
  end

  if pk && use_insert_returning?
    sql = "#{sql} RETURNING #{quote_column_name(pk)}"
  end

  [sql, binds]
end

#substitute_at(column, index) ⇒ Object 



132
133
134
 
# File 'lib/active_record/connection_adapters/postgresql/database_statements.rb', line 132

def substitute_at(column, index)
  Arel::Nodes::BindParam.new "$#{index + 1}"
end

#update_sql(sql, name = nil) ⇒ Object

Executes an UPDATE query and returns the number of affected tuples.



191
192
193
 
# File 'lib/active_record/connection_adapters/postgresql/database_statements.rb', line 191

def update_sql(sql, name = nil)
  super.cmd_tuples
end