【 tulaoshi.com - 编程语言 】
最多16列。
create table test (
f1 int,
f2 int,
f3 int,
f4 int,
f5 int,
f6 int,
f7 int,
f8 int,
f9 int,
f10 int,
f11 int,
f12 int,
f13 int,
f14 int,
f15 int,
f16 int,
f17 int
);
create index idx_test_16 on test (f1,f2,f3,f4,f5,f6,f7,f8,f9,f10,f11,f12,f13,f14,f15,f16);
create index idx_test_17 on test (f1,f2,f3,f4,f5,f6,f7,f8,f9,f10,f11,f12,f13,f14,f15,f16,f17);
运行结果如下：
mysql create table test (
- f1 int,
- f2 int,
- f3 int,
- f4 int,
- f5 int,
- f6 int,
- f7 int,
- f8 int,
- f9 int,
- f10 int,
- f11 int,
- f12 int,
- f13 int,
- f14 int,
- f15 int,
- f16 int,
- f17 int
- );
Query OK, 0 rows affected (0.06 sec)
mysql
mysql create index idx_test_16 on test (f1,f2,f3,f4,f5,f6,f7,f8,f9,f10,f11,f12,f13,f14,f15,f16);
Query OK, 0 rows affected (0.02 sec)
Records: 0 Duplicates: 0 Warnings: 0
mysql create index idx_test_17 on test (f1,f2,f3,f4,f5,f6,f7,f8,f9,f10,f11,f12,f13,f14,f15,f16,f17);
ERROR 1070 (42000): Too many key parts specified; max 16 parts allowed
mysql
