/*进阶12SQL 数据类型介绍数值型:    整数:  Tinyint(1b) < mediumint(3b)
     
      
       
        2038年     */
       
      
     

#1 溢出保护DROP TABLE IF EXISTS tab_int;CREATE TABLE tab_int(    t1 INT,    t2 INT UNSIGNED);INSERT    INTO tab_int VALUES(100000000000000,-100);  #2147483647,0DESC tab_int;SELECT * FROM tab_int;      #2 设置位数,0填充宽度CREATE TABLE tab2_int(    t1 INT(7) ZEROFILL,    t2 INT(7) UNSIGNED ZEROFILL);INSERT    INTO tab2_int VALUES(123,123);  # 0000123  , 0000123DESC tab2_int;SELECT * FROM tab2_int;    #3  测试溢出CREATE TABLE tab_float(    f1 FLOAT(5,2),    f2 DOUBLE(5,2),    f3 DECIMAL(5,2));SELECT * FROM tab_float;INSERT    INTO tab_float VALUE(123.456,123.4444,123.55);    #123.46,123.44,123.55INSERT    INTO tab_float VALUE(123.456,123.4444,123456.55); #123.46,123.44,999.99        #4 测试enum 枚举型CREATE TABLE tab_char(    row1 ENUM('a','b','c','d'));INSERT INTO tab_char VALUES('a');   #aINSERT INTO tab_char VALUES('M');   #' 'INSERT INTO tab_char VALUES('A');   #'a'SELECT * FROM tab_char;       #5 测试set 集合类型DROP TABLE  IF EXISTS tab_set;CREATE TABLE tab_set(    row1 SET('a','b','c','d'));INSERT INTO tab_set VALUES('a,c,d');   #aSELECT * FROM tab_set;    #四:日期型    CREATE TABLE tab_date(    t1 DATETIME,    t2 TIMESTAMP);INSERT INTO tab_date VALUES(NOW(),NOW());  #2018-10-29 15:13:24,2018-10-29 15:13:24SELECT * FROM tab_date;SHOW    VARIABLES LIKE 'time_zone';SET time_zone='+9:00';   # 2018-10-29 15:13:24 ,2018-10-29 16:13:24