column 'col2' at row 1 | +---+---+---+ 1 row in set (0.00 sec) mysql> insert into decimal_tb (col2) values (12.2300); Query OK, 1 row affected (0.01 sec) # 变量范围测试 # 结论:M范围是1到65,D范围是0到30,且D不大于M mysql> alter table decimal_tb add column col3 decim...
The nonstandard MySQL extension to the upper range ofDECIMALcolumns The declaration syntax for aDECIMALcolumn isDECIMAL(M,D). The ranges of values for the arguments are as follows: Mis the maximum number of digits (the precision). It has a range of 1 to 65. ...
mysql> create table t1(x float(256,30)); ERROR 1439 (42000): Display width out of range for column 'x' (max = 255) mysql> create table t1(x float(255,30)); #建表成功 Query OK, 0 rows affected (0.02 sec) mysql> create table t2(x double(255,30)); #建表成功 Query OK, 0 ...
mysql>createtabletemp2(iddouble,id2double); Query OK,0rowsaffected (0.09sec) mysql>insertintotemp2values(1.235,1,235); ERROR1136(21S01):Columncount doesn't match value count at row 1 mysql> insert into temp2 values(1.235,1.235); Query OK, 1 row affected (0.03 sec) mysql> mysql> sele...
一、MySQL 创建数据表 CREATE TABLE table_name (column_name column_type); 1. 1、创建库并设置字符集编码为utf8 create database '库名' default character set = 'utf8'; 1. 2、创建表并设置字符集编码为utf8 create table ‘表名’(id int(6),name char(10)) default character set = 'utf8';...
The nonstandard MySQL extension to the upper range ofDECIMALcolumns The declaration syntax for aDECIMALcolumn isDECIMAL(M,D). The ranges of values for the arguments are as follows: Mis the maximum number of digits (the precision). It has a range of 1 to 65. ...
set(str_arg); set_data_type(MYSQL_TYPE_NEWDECIMAL); decimals = (uint8)decimal_value.frac; fixed = true; max_length = my_decimal_precision_to_length_no_truncation( decimal_value.intg + decimals, decimals, unsigned_flag); } 在Item_decimal构造函数中调用str2my_decimal函数对输入数值进行...
mysql>droptabletemp2;QueryOK,0rowsaffected(0.16sec)mysql>createtabletemp2(iddouble,id2double);QueryOK,0rowsaffected(0.09sec)mysql>insertintotemp2values(1.235,1,235);ERROR1136(21S01):Columncountdoesn't match value count at row 1mysql> insert into temp2 values(1.235,1.235);Query OK, ...
mysql> CREATE TABLE `tc_integer` ( `f_id` bigint(20) PRIMARY KEY AUTO_INCREMENT, `f_type` tinyint, `f_flag` tinyint(1), `f_num` smallint(5) unsigned ZEROFILL ) ENGINE=InnoDB DEFAULT CHARSET=utf8; mysql> desc tc_integer; ...
那么MySQL中这三种都是浮点类型 它们彼此的区别又是什么呢 ?? float 浮点类型用于表示==单精度浮点==数值, double浮点类型用于表示==双精度浮点==数值 这里肯定有些小伙伴要问了 什么是单精度 什么是双精度 ? 下面我们就来简单了解一下吧! 我们知道一个bytes(字节) 占8位 对吧!