[摘要]CASCADE 前,要删除一个现存的列,表必须重新创建和重新装载: CREATE TABLE temp AS SELECT did, city FROM distributors; DROP ...
CASCADE }
前,要删除一个现存的列,表必须重新创建和重新装载:
CREATE TABLE temp AS SELECT did, city FROM distributors;
DROP TABLE distributors;
CREATE TABLE distributors (
did DECIMAL(3) DEFAULT 1,
name VARCHAR(40) NOT NULL,
);
INSERT INTO distributors SELECT * FROM temp;
DROP TABLE temp;
重命名列/字段和表名是 PostgreSQL 扩展。SQL92 没有提供这些。
关键词:ASP中怎样完成SQL数据库备份、恢复!