Description
Keep only the first masked-null entry and, independently, the first occurrence of each unmasked string key.
A missing-value identity can be distinct from a literal string used as a key. Stable deduplication keeps the first occurrence under the chosen identity convention.
Keep only the first masked-null entry and, independently, the first occurrence of each unmasked string key.
When to use this tool
Use List Deduplicate Caller Key Null Sentinel when you need a deduplication mask with explicit null metadata.
How to use the tool and how it works
- Enter keys, nullMask. Keep parallel arrays aligned. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read keep. Use the output convention below.
Require aligned keys and nullMask. Keep only the first masked-null entry and, independently, the first occurrence of each unmasked string key.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| keys | Keys | Required. Array of text; maximum UTF-16 length 8192; maximum items 256. |
| nullMask | Null Mask | Required. Array of boolean; maximum items 256. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| keep | Keep | Required. Array of boolean; maximum items 256. |
{
"input": {
"keys": [
"null",
"null",
"null"
],
"nullMask": [
false,
true,
false
]
},
"output": {
"keep": [
true,
true,
false
]
}
}Limitations and assumptions
- Null-mask entries share one separate identity regardless of their key text; actual null values are not inferred from strings.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
Alternative or Complementary methods
Verify how missing keys are represented and use a documented equality policy before combining actual records.
References
Similar or alternative tools
- List Sentinel Data Value Collision
Compare each value exactly with sentinel and return all zero-based indexes of matches.
- List Mask Unknown Value Count
Accept only the literal strings true, false, and unknown.