显示水果中的第3个水果,正确的命令是?
A: db.test.find({},{"fruits":{$slice:[3,1]}})
B: db.test.find({},{"fruits":{$slice:3}})
C: db.test.find({},{"fruits":{$slice:[2,1]}})
D: db.test.find({},{"fruits":{$slice:2}})
A: db.test.find({},{"fruits":{$slice:[3,1]}})
B: db.test.find({},{"fruits":{$slice:3}})
C: db.test.find({},{"fruits":{$slice:[2,1]}})
D: db.test.find({},{"fruits":{$slice:2}})
举一反三
- 以下字符串的哪些属性或方法返回的结果是number类型？（） A: substr B: slice C: indexOf D: find
- 下列Python代码，函数的定义和调用书写正确的是（） A: def test(a| b): print(a) print(b) test(1| 2) B: def test(a): print(a) print(b) test(1, 2) C: def test(a, b): print(a) print(b) test(1) D: def test(a, b): print(a) print(b) test(1, 2)
- 进行测试找到问题的原因。 A: Do the test to find the cause of the problem. B: Do the test to make the cause of the problem apparent. C: Do the test to decide about the reason of the problem. D: Do the test to detect the reason of the problem.
- If the test takers find an item to which an answer is not known, it may be _______ to leave it blank and go on with the test.
- >> test(1:3,[-1,0,3])