Matches a value in the CSV file or through a limited form of JSON file, uploaded using Lookup Files.

columnstringoptional[a]field parameter Which column in the file to use for the match. A single column or an array or columns can be specified.
fieldstringrequired  Which field in the event (log line) must match the given column value. A single field or an array or fields can be specified. Field and column must have the same length, are matched in order and must all match.
file[b]stringrequired  Specifies the source file.
glob (deprecated)booleanoptional[a]false This parameter is deprecated. Use mode=glob instead. (deprecated in 1.23.0)
ignoreCasebooleanoptional[a]false If true, ignore case when matching against the CSV data.
includestring or arrayoptional[a]  The columns to include. If no argument is given, include all columns from the corresponding row in the output event.
modestringoptional[a]string The function to use when matching against keys.
  Valid Values
   cidrThe key is interpreted as a CIDR subnet and the event is matched if the field contains an IP within the subnet. If multiple subnets match, the most specific one is selected or an arbitrary one if there are multiple equally specific subnets.
   globThe key is interpreted as a globbing pattern with * and matched accordingly e.g. a CSV key value of *thisMatch* would match the field value of 123thisMatch456.
   stringThe matching is done using exact string matching.
strictbooleanoptional[a]true If true (the default) selects only the fields that match a key in the file; if false lets all events through (works like the deprecated lookup()).

[a] Optional parameters use their default value unless explicitly set

[b] The argument name file can be omitted.

Omitted Argument Names

The argument name for file can be omitted; the following forms of this function are equivalent:




These examples show basic structure only; full examples are provided below.

When lookup information from files are loaded from a package, the package name should be specified in addition to the filename. For example:


For more information on referring to package resources, see Referencing Package Assets.

The default behavior of this function — when strict is set to true — works like an INNER JOIN. When strict is set to false the function enriches events.


Up until LogScale version 1.140, the file is limited to 1,000,000 rows/lines for exact matching using mode=string.

When using mode=glob, the underlying CSV is limited to 20,000 rows/lines.

For self-hosted customers, the maximum value for glob matches is configurable using GLOB_MATCH_LIMIT.

match() File Formats

For Comma Separated Values (CSV) files, whitespace gets included in the keys and values. To include the separator "," in a value, quote using the " character. The following file is a valid CSV file:


The first line is intepreted as the column title. When querying, the column in the field should be used to identify which column to match against.

When using match() with a single column:

match(test.csv, fields=somefield, column=column1)

the last matching row in test.csv is used.


For JSON files, two formats are supported:

  • Object-based, where the lookup field does not have an explicit name

  • Array-based, where the information is an array of objects

In the Object-based variant, the lookup values are declared as an object with a key and embedded fields, the key field does not have a name.

  "1": { "name": "chr" },
  "2": { "name": "krab" },
  "4": { "name": "pmm" },
  "7": { "name": "mgr" }

When matching against a file in this case, the name of the field in the JSON object does not need to be used; the key for each value is used instead. For example:

| count(@timezone)
| match(file="short.json",field=_count)

In the above, the value of _count will be matched, outputting the match value:


In the array-based variant, the lookup values are declared as an array of objects, you select which field is the key using the field parameter in match().

  { "userid": "1", "name": "chr" },
  { "userid": "2", "name": "krab" },
  { "userid": "4", "name": "pmm" },
  { "userid": "7", "name": "mgr" }

When using this version, the name of the column to be matched must be specified using the column argument to match():

| count(@timezone)
| match(file="long.json",field=_count,column="userid")

This behavior also means that any field in the JSON file can be used as the match value. For example:

| match(file="long.json",field=codename,column="name")

This can be useful if you have a JSON file that contains multiple possible lookup values for given records.



The match() does not report an error if the file format cannot be parsed.

match() Examples

Matches events for which the id field matches the value of the column in the table "users.csv". Does not add any columns.

match(file="users.csv", column=userid, field=id, include=[])

Matches events for which the id field is matched case-insensitive by the glob-pattern in the column userid in the table users.csv, and add all other columns of the first matching row to those events.

id =~ match(file="users.csv", column=userid, mode=glob, ignoreCase=true)

Let all events pass through, but events for which the id field matches the value of the userid column in the table users.csv will be enriched with all other columns of the matching row.

id =~ match(file="users.csv", column=userid, strict=false)

Matches events for which the ip field matches the CIDR subnet of the cidr-block column in the table cidr-file.csv. Only adds the columns info and type from the first matching row.

match(file="cidr-file.csv", column="cidr-block", field=ip, mode=cidr, include=["info","type"])