文件名称：日期的计算-SQL语言基础
文件大小：5.26MB
文件格式：PPT
更新时间：2024-05-15 13:24:54
SQL 基础
日期的计算 * 为一个日期值增加或者减少一个数字. 计算出两个日期之间相隔的天数. 要为日期值增加小时数，可以将小时数除以24后加上。 * Arithmetic with Dates Since the database stores dates as numbers, you can perform calculations using arithmetic operators such as addition and subtraction. You can add and subtract number constants as well as dates. You can perform the following operations: