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Jun 07, 2016 pm 03:07 PM

oracledatadatabasecoretype

Oracle数据库的核心是表，表中的列使用到的常见数据类型如下： CHAR(length) 存储固定长度的字符串。参数length指定了长度，如果存储的字符串长度小于length，用空填充。默认长度是1，最长不超过2000字节。 VARCHAR2(length) 存储可变长度的字符串。length

Oracle数据库的核心是表，表中的列使用到的常见数据类型如下：
CHAR(length)
存储固定长度的字符串。参数length指定了长度，如果存储的字符串长度小于length，用空格填充。
默认长度是1，最长不超过2000字节。
VARCHAR2(length)
存储可变长度的字符串。length指定了该字符串的最大长度。默认长度是1，最长不超过4000字符。
NUMBER(p，s)
既可以存储浮点数，也可以存储整数，p表示数字的最大位数（如果是小数包括整数部分和小数部分
和小数点，p默认是38为），s是指小数位数。
DATE
存储日期和时间，存储纪元、4位年、月、日、时、分、秒。
TIMESTAMP
不但存储日期的年月日，时分秒，以及秒后6位，同时包含时区。
CLOB
存储大的文本，比如存储非结构化的XML文档
BLOB
存储二进制对象，如图形、视频、声音等。

示例：

格式                        输入的数字         实际的存储
NUMBER                1234.567         1234.567
NUMBER（6，2） 123.4567         123.46
NUMBER（4，2） 12345.67         输入的数字超过了所指定的精度，数据库不能存储

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