在SQL中,update语句的功能是更新表中已有数据记录的内容。 1、单表更新 单表更新一个字段: 单表同时更新多个字段: 2、多表关联更新 2.1 PgSQL数据库语法结构: 具体示例如下所示:脚本作用是更新表order_item的product_name字段内容 2.2 MySQL数据库语法结构1: 2.3 MySQL数据库语法结构2:update功能
update语法结构
UPDATE table_name
SET column_name = value
WHERE condition
UPDATE table_name
SET column1 = value1, column2 = value2
WHERE condition1
AND condition2
UPDATE table_name1
SET column1 = value1, column2 = value2
FROM table_name2
WHERE condition1
AND condition2
UPDATE order_item
SET product_name = product.product_name
FROM product
WHERE product.status is TRUE
AND order_item.sku_code = product.sku_code
UPDATE table_name1,table_name2
SET table_name1.column1 = value1
WHERE condition1
AND condition2
UPDATE table_name1 INNER JOIN table_name2
ON table_name1.column1 = table_name2.column1
SET table_name1.column2 = value2