Calculates a hash value over the function arguments, producing a value in the range
0 <= x < 263.
HASH function is typically used to segment a projection over a set of cluster nodes. The function selects a specific node for each row based on the values of the row columns. The
HASH function distributes data evenly across the cluster, which facilitates optimal query execution.
HASH ( expression-arg[,… ] )
|expression‑arg||An expression of any data type. Functions that are included in expression must be deterministic. If specified in a projection's hash segmentation clause, each expression typically resolves to a column reference.|
=> SELECT HASH(product_price, product_cost) FROM product_dimension WHERE product_price = '11'; hash --------------------- 4157497907121511878 1799398249227328285 3250220637492749639 (3 rows)