Class: ActiveRecord::ConnectionAdapters::PostgreSQL::SchemaStatements::SequenceReset

# File 'activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb', line 351

def backfill_max_values
  tables_without_max_or_min_values = @tables.select { |table, data| !data.max_value || !data.min_value }.keys

  return unless tables_without_max_or_min_values.any?

  tables_max_value_sqls = tables_without_max_or_min_values.map do |table|
    sequence = @tables[table].sequence
    column = @tables[table].column
    sequence ? select_max_column_value_sql(table, column) : nil
  end
  max_values = tables_max_value_sqls.map { |sql| @adapter.query_value(sql, "SCHEMA") if sql }

  tables_without_max_or_min_values.zip(max_values).each do |table, max_value|
    @tables[table].max_value = max_value
  end
end

# File 'activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb', line 368

def backfill_min_values
  tables_without_max_or_min_values = @tables.select { |table, data| !data.max_value || !data.min_value }.keys

  return unless tables_without_max_or_min_values.any?

  tables_min_value_sqls = tables_without_max_or_min_values.map do |table|
    sequence = @tables[table].sequence
    sequence ? select_min_column_value_sql(sequence) : nil
  end
  min_values = tables_min_value_sqls.map { |sql| @adapter.query_value(sql, "SCHEMA") if sql }

  tables_without_max_or_min_values.zip(min_values).each do |table, (min_value)|
    @tables[table].min_value = min_value
  end
end

# File 'activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb', line 319

def backfill_sequences_with_primary_keys
  tables_without_sequences = @tables.select do |table, data|
    !data.column || !data.sequence
  end.keys

  return if tables_without_sequences.none?

  sql = primary_key_column_and_sequence_sql(tables_without_sequences)
  primary_key_column_and_sequences = @adapter.exec_query(sql, "SCHEMA")

  primary_key_column_and_sequences.rows.each do |table, column, namespace, sequence|
    @tables[table].column = column
    @tables[table].sequence = PostgreSQL::Name.new(namespace, sequence) if sequence
  end
end

# File 'activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb', line 335

def backfill_sequences_with_uuids
  tables_without_sequences = @tables.select do |table, data|
    !data.column || !data.sequence
  end.keys

  return if tables_without_sequences.none?

  sql = uuid_column_and_sequence_sql(tables_without_sequences)
  uuid_column_and_sequences = @adapter.exec_query(sql, "SCHEMA")

  uuid_column_and_sequences.rows.each do |table, column, namespace, sequence|
    @tables[table].column = column
    @tables[table].sequence = PostgreSQL::Name.new(namespace, sequence) if sequence
  end
end

# File 'activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb', line 384

def primary_key_column_and_sequence_sql(tables)
  <<~SQL
  SELECT tables.name, attr.attname, nsp.nspname, seq.relname
  FROM (VALUES #{tables_values_sql(tables)}) AS tables (name, oid),
      pg_class      seq,
      pg_attribute  attr,
      pg_depend     dep,
      pg_constraint cons,
      pg_namespace  nsp
  WHERE seq.oid           = dep.objid
    AND seq.relkind       = 'S'
    AND attr.attrelid     = dep.refobjid
    AND attr.attnum       = dep.refobjsubid
    AND attr.attrelid     = cons.conrelid
    AND attr.attnum       = cons.conkey[1]
    AND seq.relnamespace  = nsp.oid
    AND cons.contype      = 'p'
    AND dep.classid       = 'pg_class'::regclass
    AND dep.refobjid      = tables.oid
  SQL
end

# File 'activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb', line 300

def reset
  backfill

  reset_sqls = @tables.values.filter_map do |data|
    next unless data.sequence && (data.max_value || data.min_value)
    reset_sequence_sql(data.sequence, data.max_value, data.min_value)
  end

  @adapter.execute_batch(reset_sqls, "SCHEMA")
end

# File 'activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb', line 443

def reset_sequence_sql(sequence, max_value, min_value)
  quoted_sequence = @adapter.quote_table_name(sequence)
  "SELECT setval(#{@adapter.quote(quoted_sequence)}, #{max_value || min_value}, #{max_value ? true : false})"
end

# File 'activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb', line 434

def select_max_column_value_sql(table, column)
  "SELECT MAX(#{@adapter.quote_column_name(column)}) FROM #{@adapter.quote_table_name(table)}"
end

# File 'activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb', line 438

def select_min_column_value_sql(sequence)
  quoted_sequence = @adapter.quote_table_name(sequence)
  "SELECT seqmin FROM pg_sequence WHERE seqrelid = #{@adapter.quote(quoted_sequence)}::regclass"
end

# File 'activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb', line 428

def tables_values_sql(tables)
  tables.map do |table|
    "(#{@adapter.quote(table)}, #{@adapter.quote(@adapter.quote_table_name(table))}::regclass)"
  end.join(", ")
end

# File 'activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb', line 406

def uuid_column_and_sequence_sql(tables)
  <<~SQL
  SELECT tables.name, attr.attname, nsp.nspname,
    CASE
      WHEN pg_get_expr(def.adbin, def.adrelid) !~* 'nextval' THEN NULL
      WHEN split_part(pg_get_expr(def.adbin, def.adrelid), '''', 2) ~ '.' THEN
        substr(split_part(pg_get_expr(def.adbin, def.adrelid), '''', 2),
               strpos(split_part(pg_get_expr(def.adbin, def.adrelid), '''', 2), '.')+1)
      ELSE split_part(pg_get_expr(def.adbin, def.adrelid), '''', 2)
    END
  FROM (VALUES #{tables_values_sql(tables)}) AS tables (name, oid)
  JOIN pg_class       t    ON (t.oid = tables.oid)
  JOIN pg_attribute   attr ON (t.oid = attrelid)
  JOIN pg_attrdef     def  ON (adrelid = attrelid AND adnum = attnum)
  JOIN pg_constraint  cons ON (conrelid = adrelid AND adnum = conkey[1])
  JOIN pg_namespace   nsp  ON (t.relnamespace = nsp.oid)
  WHERE cons.contype = 'p'
    AND pg_get_expr(def.adbin, def.adrelid) ~* 'nextval|uuid_generate|gen_random_uuid'
  SQL
end