Do you use the transpose command like following?
index=_internal | stats count by sourcetype | transpose 7
you can use eval command and chart command instead of using the transpose command
try this search
index=_internal | stats count by sourcetype
| eval a=if(sourcetype="mongod","test1",a)
| eval a=if(sourcetype="scheduler","test2",a)
| eval a=if(sourcetype="splunk_web_access","test3",a)
| eval a=if(sourcetype="splunk_web_service","test4",a)
| eval a=if(sourcetype="splunkd","test5",a)
| eval a=if(sourcetype="splunkd_access","test6",a)
| eval a=if(sourcetype="splunkd_ui_access","test7",a)
| eval column="percent"
| chart values(count) by column,a
sorry if Q0=A, then column name = text1, if Q0= B then column name = text2. Since I have sort the Q0, so the order of A B C D E would be change automatically, that is why I need use Q0 as a condition to rename column name.