does the number of column affect performance

[Zheng Li]

for example
there are 2 tables to save same data
table A has 10 columns: a primary key column and 9 blob column
table B has 2 columns : a primary key column and 1 blob column which includes all data in
2nd~10th columns of table A

are there any differences in performance when selecting, inserting, updating, and deleting
data.