#include <stdio.h>#include <math.h> int main(){ double a = 10.0,b = 3.0; float c; c = pow(a,b); printf("%f\n",c);}编译结果:/tmp/ccibw7gz.o: In function `main':test.c:(.text+0x2d): undefined reference to `pow'c…
update字段中带select UPDATE tb_report_type A INNER JOIN (SELECT LEVEL_CODE FROM tb_report_type WHERE id = 'ED894BE001CE4F47A2916287A491B4E1') BSET A.LEVEL_CODE = CONCAT(B.LEVEL_CODE,'-',A.id) WHERE A.PARENT_ID = 'ED894BE001CE4F47A2916287A491B4E1'…