我如何添加一个新列来将行数作为序列号进行计数

问题描述

record of
id  fare    commission  routecode   vehicle number  productcode date    time    driver  owner name
15  12345   123 4533    1   3344    2011-03-18  00:00:00    yasir   saleem
20  a   a   3433    1   2333    2011-03-25  00:00:00    yasir   saleem
36  11111   11111   3433    1   2333    2011-03-25  16:13:12    yasir   saleem
9   1233    123 3433    nk-234  2333    2011-03-24  00:00:00    siddiq  aslam
21  1200    120 4533    nk-234  7655    2011-03-24  00:00:00    siddiq  aslam
22  1200    133333  0987    nk-234  2333    2011-03-11  00:00:00    siddiq  aslam
23  10000   11  4533    nk-234  7655    2011-03-19  00:00:00    siddiq  aslam
25  122 12  0987    nk-234  2333    2011-03-11  00:00:00    siddiq  aslam
26  1000    100 3344    nk-234  7655    2011-03-11  00:00:00    siddiq  aslam
27  1000    100 3344    nk-234  2333    2011-03-10  00:00:00    siddiq  aslam
34  100 10  3344    nk-234  2333    2011-03-18  00:00:00    siddiq  aslam
35  100 10  3344    nk-234  2333    2011-03-02  00:00:00    siddiq  aslam
5   1000    100 1234    wq1233  3344    2011-03-10  22:30:00    waqas   sami
6   2222    22  1234    wq1233  3344    2011-03-17  22:30:00    waqas   sami
24  a   a   4533    PSS-1234    7655    2011-03-02  00:00:00    salman  salam
42633   145175

我想在id之前添加另一列，以计算

I want to add another column before id which counts the number of

行.它应该从1开始，然后每行增加1.

rows. It should start from 1 and increment by 1 for each row.

推荐答案

如果在SELECT语句中表示:

If you mean in a SELECT statement:

说您的选择是

select * from tbl

它变成

select @n := @n + 1 RowNumber, t.*
from (select @n:=0) initvars, tbl t

注意:

1. select @n:=0用于将全局变量重置为0
2. @n := @n + 1每行从1开始将其增加1.此列名为"RowNumber"

1. select @n:=0 is used to reset the global variable to 0
2. @n := @n + 1 increases it by 1 for each row, starting from 1. This column is named "RowNumber"

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