MURMUR_HASH_64 - Realtime Compute for Apache Flink - Alibaba Cloud Documentation Center

The topic describes how to use the MURMUR_HASH_64 function. This function specifies the 64-bit hash value for a parameter by using the hash128x64 method.

Limits

This function is supported only in Realtime Compute for Apache Flink that uses Ververica Runtime (VVR) 3.0.0 or later.

Syntax

BIGINT MURMUR_HASH_64(value)

Input parameters

Parameter	Data type
value	VARCHAR or a numeric value

Examples

Example 1

Test data
Table 1 T1
id(INT)
hash_64_value(VARCHAR)
1
This is a test String.
2
null
3
test

Table 1 T1
id(INT)	hash_64_value(VARCHAR)
1	This is a test String.
2	null
3	test

Test statement

SELECT id,MURMUR_HASH_64(hash_64_value) as big
FROM T1;

Test result
id(INT)
big(BIGINT)
1
2706826604463635000
2
-
3
5010266691562018000

Example 2

Test data
Table 2. T2
id(INT)
hash_64_value(FLOAT)
1
4.5
2
NULL
3
4

Table 2. T2
id(INT)	hash_64_value(FLOAT)
1	4.5
2	NULL
3	4

Test statement

SELECT MURMUR_HASH_64(hash_64_value) as big
FROM T2;

Test result
id(INT)
big(BIGINT)
1
8033179276572535000
2
-
3
-6697622088025985000

References

For more information about how to specify the 32-bit hash value for a parameter by using the hash32x86 method, see MURMUR_HASH.

id(INT)	big(BIGINT)
1	2706826604463635000
2	-
3	5010266691562018000

id(INT)	big(BIGINT)
1	8033179276572535000
2	-
3	-6697622088025985000