必须在查询准备时间定义枢轴查询的列数。 To achieve dynamic cross-tabulation, you have two options that involve writing application code:

Option 1: Query Distinct Values and Construct Dynamic SQL

Create an array of SQL fragments representing the maximum对于每个不同维度值的时间。

; $ way_array [] =“ max（if（`way` = $ way，`time'））为way_ $ way'; } $ pivotsql =“ select stop”。加入（“，”，$ Way_array）。 “从`fore of'of`of ot ot ot of ot ot of ot o of ot o of ot o';

example：; 如果（！array_key_exists（$ stopkey，$ stoparray））{ $ stoparray [$ stopkey] = array（“ stop” => $ stopkey）; } $ waykey =“ way_”。 $ row [“ Way”]; $ stoparray [$ stopkey] [$ waykey] = $ row [“ time”]; }