Lu, Huayi e6fa411af0 DWS DEV 830.201 version

Reviewed-by: Pruthi, Vineet <vineet.pruthi@t-systems.com>
Co-authored-by: Lu, Huayi <luhuayi@huawei.com>
Co-committed-by: Lu, Huayi <luhuayi@huawei.com>

2024-05-16 07:24:04 +00:00

15 KiB

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HLL Operators

The HLL type supports the following operators:

Table 1 HLL Operators

HLL Operators

Description

Return Type

Example

Checks whether the values of hll and hll_hashval are equal.

bool

1
2
3
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5
SELECT (hll_empty() || hll_hash_integer(1)) = (hll_empty() || hll_hash_integer(1));
 ?column?
----------
 t
(1 row)

hll_hashval

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2
3
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5
SELECT hll_hash_integer(1) = hll_hash_integer(1);
 ?column? 
----------
 t
(1 row)

<> or !=

Checks whetherthe values of hll and hll_hashval are not equal.

bool

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2
3
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5
SELECT (hll_empty() || hll_hash_integer(1)) <> (hll_empty() || hll_hash_integer(2));
 ?column? 
----------
 t
(1 row)

hll_hashval

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3
4
5
SELECT hll_hash_integer(1) <> hll_hash_integer(2);
 ?column? 
----------
 t
(1 row)

Represents the functions of hll_add, hll_union, hll_add_rev.

hll

hll_add

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SELECT hll_empty() || hll_hash_integer(1);
         ?column?         
--------------------------
 \x128b7f8895a3f5af28cafe
(1 row)

hll_add_rev

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SELECT hll_hash_integer(1) || hll_empty();
         ?column?         
--------------------------
 \x128b7f8895a3f5af28cafe
(1 row)

hll_union

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SELECT (hll_empty() || hll_hash_integer(1)) || (hll_empty() || hll_hash_integer(2));
                 ?column?                 
------------------------------------------
 \x128b7f8895a3f5af28cafeda0ce907e4355b60
(1 row)

Calculates the distinct value of the hll. It is the same as that of the hll_cardinality function.

integer

1
2
3
4
5
SELECT #(hll_empty() || hll_hash_integer(1));
 ?column? 
----------
        1
(1 row)

Parent topic: HLL Functions and Operators

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HLL Operators

15 KiB

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