## layout: doc_page

# Sketch Features Matrix

Use the following table to compare the capabilities of the different sketch families.

All sketches have *a posteriori* error bounds methods.

1 Integrated into Druid.

2 Spark Example Code on website. Theta Sketch is the only one we have tried in Spark, it doesn't mean other sketches cannot be used.

3 Tuple Sketch: Example Code in test/.../tuple/aninteger.

4 Theta Sketch: C++/Python has no implementaion of the Jaccard, yet.

5 Frequent Items Sketch: PostgreSQL implemented for Strings only.

6 KLL & REQ Sketch: Python implemented for both just floats and ints.

7 See Python Install Instructions

## Definitions

### Type

See Research/References for references in [...]

**Cardinality/CPC** Implementation and extension of [LAN17].**Cardinality/HLL** Derivation and extension of [FFGM07]**Cardinality/Theta** Derivation and extension of [DLRT16].**Cardinality/Tuple** An Extension of the Theta family that adds attributes to each hash-key.**Quantiles/Cormode** Derivation and extension of [AC+13]**Quantiles/KLL** Derivation and extension of [KLL16].**Frequencies** Derivation and extension of [ABL+17].**Sampling/Reservior** Derivation and extension of [K98], Vol 2, Section 3.4.2, Algorithm R.**Sampling/VarOpt** Derivation and extension of [CDKLT09].