谁能解释一下下面的行为？

import pyspark.pandas as ps

loan_information = ps.read_sql_query([blah])

loan_information.shape
#748834, 84

loan_information.apply(lambda col: col.shape)
#Each column has 75 dimensions. The first 74 are size 10000, the last is size 8843
#This still sums to 748834, but hardly seems like desirable behavior

我的猜测是，批量大小为10000的文件被提供给了执行程序，但是，这似乎是非常不受欢迎的行为。