This is a task converting text into SQL statement. We will first given the dataset schema and then ask a question in
text. You are asked to generate SQL statement.
[Schema]:
CREATE TABLE `dws_energy_electric` (
  `org_code` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NOT NULL COMMENT '基地数字编码',
  `days` datetime(6) DEFAULT NULL COMMENT '用能日期，例如：2011-01-03',
  `edc_consumption` decimal(10,0) DEFAULT NULL COMMENT '能源消耗量，例如：99.8',
  `edc_cost` decimal(10,0) DEFAULT NULL COMMENT '用能花费金额，例如：155',
  `edc_period_type` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci DEFAULT NULL COMMENT '用电单价时段类别，例如''尖峰''等',
  KEY `dws_electric_energy_consume_group_consume_ibfk_1` (`org_code`) USING BTREE,
  CONSTRAINT `dws_energy_electric_ibfk_1` FOREIGN KEY (`org_code`) REFERENCES `dim_pub_organization_layered` (`org_code`) ON DELETE RESTRICT ON UPDATE RESTRICT
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci ROW_FORMAT=DYNAMIC;
[Question]:
2012年用电量的标准差是多少？
Please generate a right SQL statement according the dataset schema and question.