Parse a key-value pair string by using the KEYVALUE function - MaxCompute

Extracts the value of a specified key from a key-value pair string. The function splits the input string into key-value pairs using split1, separates keys from values using split2, and returns the value that matches the given key.

Syntax

KEYVALUE(STRING <str>, [STRING <split1>, STRING <split2>,] STRING <key>)
KEYVALUE(STRING <str>, STRING <key>)

Parameters

Parameter	Required	Description
`str`	Yes	The input string to parse.
`split1`	No	The delimiter that separates key-value pairs. Defaults to a semicolon (`;`).
`split2`	No	The delimiter that separates keys from values within each pair. Defaults to a colon (`:`).
`key`	Yes	The key whose corresponding value is returned.

If a key-value pair (after splitting by split1) contains multiple occurrences of split2, the return value is undefined for that pair.

Return value

Returns a value of the STRING type. The return value follows these rules:

Returns null if split1 or split2 is null.
Returns null if str or key is null, or if no matching key is found.
Returns the value of the first matching key if multiple key-value pairs share the same key.

Examples

Use default delimiters

Split 0:1\;1:2 and return the value for key 1. Because split1 and split2 are not specified, the function uses the defaults: semicolon (;) as the pair delimiter and colon (:) as the key-value delimiter.

-- Returns 2.
SELECT KEYVALUE('0:1\;1:2', 1);

After splitting by ;, the key-value pairs are:

0  1\
1  2

The value for key 1 is 2.

Use custom delimiters

Split \;decreaseStore:1\;xcard:1\;isB2C:1\;tf:21910\;cart:1\;shipping:2\;pf:0\;market:shoes\;instPayAmount:0\; using \; as the pair delimiter and : as the key-value delimiter, then return the value for key tf.

-- Returns 21910.
SELECT KEYVALUE("\;decreaseStore:1\;xcard:1\;isB2C:1\;tf:21910\;cart:1\;shipping:2\;pf:0\;market:shoes\;instPayAmount:0\;","\;",":","tf");

After splitting by \;, the key-value pairs are:

decreaseStore  1
xcard          1
isB2C          1
tf             21910
cart           1
shipping       2
pf             0
market         shoes
instPayAmount  0

The value for key tf is 21910.

Related functions

KEYVALUE is a string function. For a full list of string search and conversion functions, see String functions.