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【DM版本】:V8
【操作系统】:
【CPU】:
【问题描述】*:如何实现
CREATE TABLE stat_producer_daily
(
company_id
varchar(9) DEFAULT NULL,
update_date
datetime DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP COMMENT '更新时间',
update_user
varchar(32) DEFAULT NULL,
PRIMARY KEY (company_id
) USING BTREE
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;
建表语句可以这样改下,看下是否满足您要求:
CREATE TABLE "ex_departments" (
"id" INT IDENTITY(1, 1) NOT NULL PRIMARY KEY,
"name" VARCHAR(32) NOT NULL,
"parent_id" INT,
"default" BIT DEFAULT 0,
"description" VARCHAR(255),
"created_at" DATETIME DEFAULT CURRENT_TIMESTAMP,
"updated_at" DATETIME DEFAULT CURRENT_TIMESTAMP ON UPDATE NOW(),
FOREIGN KEY ("parent_id") REFERENCES "ex_departments"("id") ON DELETE SET NULL
);
ALTER TABLE stat_station_heat_year
modify update_date datetime;
ALTER TABLE stat_station_heat_year
modify update_date DEFAULT CURRENT_TIMESTAMP ON UPDATE NOW();
改成这样
create table t2(
c1 varchar2(100),
c2 datetime DEFAULT CURRENT_TIMESTAMP ON UPDATE NOW()
);