Professional orchestras have auditions, where you will perform a piece from the solo repertoire in front of the head of the section you are auditioning for, and a few other key staff (e.g. [1]). Some auditions will include orchestral parts, and you can buy books of famous solos for most instruments.
This repertoire has little in common with the kind of playing you will be paid for, other than as a pure display of technical ability (just like whiteboarding). For example, it is relatively poor as a gauge of the ability to play with others (accompanists follow you, not the other way around), or of your fitting in with the rest of your section.
Even on a technical level, performing a showy piece well in the few minutes of the audition does not mean you have the stamina to sustain this playing through four hours of Wagner.
[1] "The jury consists of 25 members of the orchestra: two of four concertmasters, the principals, the VPO chairman and managing director, five musicians of the relevant orchestra section, two staff council members from the Vienna State Opera Orchestra, and a representative of the Vienna State Opera’s management." - http://web.archive.org/web/20141203022823/http://slippedisc....