|| (arrays and objects)

Concatenates arrays or merges objects with the || operator.

Syntax

<left> || <right> [|| <next> ...]

Arguments

Returns

Returns the same type as the inputs.

• Arrays preserve element order, duplicates, and NULL elements.
• Objects combine their top-level keys. For duplicate keys, the right-hand value replaces the left-hand value, including nested objects.
• If any input is NULL, returns NULL.

Examples

Combine event labels

Combine labels from an event and an investigation. Concatenation preserves both order and duplicates.

SELECT ['checkout', 'timeout'] || ['timeout', 'reviewed'] AS labels

The labels value:

[
  "checkout",
  "timeout",
  "timeout",
  "reviewed"
]

Use dedup on the combined array when the result should contain each label only once.

Apply event-specific attributes

Merge shared context with event-specific attributes. The right-hand object overrides a shared key.

SELECT
    {'region': 'apac', 'channel': 'web'} ||
    {'channel': 'mobile', 'campaign': 'spring'} AS attributes

The attributes value:

{
  "campaign": "spring",
  "channel": "mobile",
  "region": "apac"
}

The resulting channel is mobile; region is retained from the left-hand object.