Bitmap index including internal metadata storage

1. A method comprising:

receiving a first signal at a computing device comprising a processor;

updating a bitmap index responsive to the first signal, wherein the bitmap index is distributed across a plurality of storage devices, and wherein the bitmap index includes a plurality of bit strings, wherein a value stored in a particular location in each of the bit strings indicates whether a corresponding signal associated with a signal source has been received, and wherein updating the bitmap index responsive to the first signal includes updating a first bit of the bitmap index and updating a first metadata value stored in the bitmap index;

receiving a second signal at the computing device; and

updating the bitmap index responsive to the second signal, wherein updating the bitmap index responsive to the second signal includes updating a second bit of the bitmap index and updating a second metadata value stored in the bitmap index.

2. The method of claim 1 , wherein:

the first metadata value corresponds to at least one bit string of the plurality of bit strings,

the second metadata value corresponds to at least one signal source of a plurality of signal sources, or

a combination thereof.

3. The method of claim 1 , further comprising generating query results based on a query, wherein the query results identify at least one signal associated with at least one bit string of the plurality of bit strings, at least one signal source of a plurality of signal sources, and at least one of the first metadata value or the second metadata value.

4. The method of claim 1 , wherein the first metadata value and the second metadata value are part of respective name-value pairs included in the bitmap index.

5. The method of claim 1 , wherein the first metadata value corresponds to a count of signal sources for which a corresponding signal has been received.

6. The method of claim 1 , wherein the first metadata value corresponds to a sort index.

7. The method of claim 1 , wherein a plurality of bitmap indexes are associated with a plurality of websites, and wherein the first metadata value is based on a comparison of a popularity of a signal with respect to a website and a popularity of the signal with respect to the plurality of websites.

8. The method of claim 1 , wherein the signal source corresponds to a user, a computing device associated with the user, or a computing device not associated with any user.

9. The method of claim 1 , wherein the second metadata value corresponds to user contact information.

10. The method of claim 3 , wherein the query results are sorted based on at least one of the first metadata value or the second metadata value.

11. The method of claim 1 , wherein the bitmap index represents data stored in a data store.

12. The method of claim 11 , wherein the data stored in the data store is determined based at least in part on event signals received from devices associated with a plurality of users.

13. The method of claim 1 , wherein one or more of the plurality of bit strings corresponds to a demographic attribute, a behavior, a brand affinity, or a combination thereof.

14. The method of claim 1 , wherein each of the plurality of bit strings is stored as one or more distributed slices, and wherein at least a first slice of a particular bit string of the plurality of bit strings is stored in a different storage device than a second slice of the particular bit string.

15. The method of claim 3 , further comprising generating a query execution plan for the query, wherein the query execution plan identifies:

one or more set operations;

that one or more first storage nodes are to send stored portions of one or more bit strings to a second storage node; and

that the second storage node is to perform the one or more set operations with respect to:

the portions of the one or more bit strings received from the one or more first storage nodes; and

portions of one or more bit strings stored at the second storage node; and

that the second storage node is to concatenate results of performing the one or more set operations to generate a result bit string that indicates a result of the query.

16. The method of claim 15 , wherein the query results are determined without accessing a lookup table that is external to the bitmap index.

17. An apparatus comprising:

a processor; and

a memory storing instructions executable by the processor to perform operations comprising:

receiving a first signal;

updating a bitmap index responsive to the first signal, wherein the bitmap index is distributed across a plurality of storage devices, and wherein the bitmap index includes a plurality of bit strings, wherein a value stored in a particular location in each of the bit strings indicates whether a corresponding signal associated with a signal source has been received, and wherein updating the bitmap index responsive to the first signal includes updating a first bit of the bitmap index and updating a first metadata value stored in the bitmap index;

receiving a second signal; and

updating the bitmap index responsive to the second signal, wherein

updating the bitmap index responsive to the second signal includes updating a second bit of the bitmap index and updating a second metadata value stored in the bitmap index.

18. The apparatus of claim 17 , wherein the first metadata value and the second metadata value are part of respective name-value pairs included in the bitmap index, wherein the first metadata value corresponds to a count of users for whom a corresponding signal has been received, a sort index, or a comparison of a popularity of a signal with respect to a website and a popularity of the signal with respect to a plurality of websites, and wherein the second metadata value corresponds to user contact information.

19. A computer-readable storage device storing instructions that,

when executed, cause a computer to perform operations comprising:

receiving a first signal;

updating a bitmap index responsive to the first signal, wherein the bitmap index is distributed across a plurality of storage devices, and wherein the bitmap index includes a plurality of bit strings, wherein a value stored in a particular location in each of the bit strings indicates whether a corresponding signal associated with a signal source has been received, and wherein updating the bitmap index responsive to the first signal includes updating a first bit of the bitmap index and updating a first metadata value stored in the bitmap index;

receiving a second signal; and

updating the bitmap index responsive to the second signal, wherein updating the bitmap index responsive to the second signal includes updating a second bit of the bitmap index and updating a second metadata value stored in the bitmap index.