strings.hasPrefix() function

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strings.hasPrefix() indicates if a string begins with a specified prefix.

Function type signature

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Parameters

v

({{< req >}}) String value to search.

prefix

({{< req >}}) Prefix to search for.

Examples

Filter based on the presence of a prefix in a column value

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Input data

_time	*tag	_value
2021-01-01T00:00:00Z	t1	smpl_g9qczs
2021-01-01T00:00:10Z	t1	smpl_0mgv9n
2021-01-01T00:00:20Z	t1	smpl_phw664
2021-01-01T00:00:30Z	t1	smpl_guvzy4
2021-01-01T00:00:40Z	t1	smpl_5v3cce
2021-01-01T00:00:50Z	t1	smpl_s9fmgy

_time	*tag	_value
2021-01-01T00:00:00Z	t2	smpl_b5eida
2021-01-01T00:00:10Z	t2	smpl_eu4oxp
2021-01-01T00:00:20Z	t2	smpl_5g7tz4
2021-01-01T00:00:30Z	t2	smpl_sox1ut
2021-01-01T00:00:40Z	t2	smpl_wfm757
2021-01-01T00:00:50Z	t2	smpl_dtn2bv

Output data

_time	*tag	_value
2021-01-01T00:00:40Z	t1	smpl_5v3cce

_time	*tag	_value
2021-01-01T00:00:20Z	t2	smpl_5g7tz4

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