> ## Documentation Index
> Fetch the complete documentation index at: https://www.activepieces.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.
# Data Manipulation
> Transform and combine data inside any text input using data manipulation
## Why data manipulation
[Passing data](./passing-data) lets you insert values from previous steps into the current step's inputs. Data manipulation lets you **transform that data** before it gets used — combine two values into one, change the format, do a calculation, fall back to a default when something is empty, or branch on a condition.
If a mention answers *"which value goes here?"*, a data manipulation function answers *"what should I do with that value first?"*.
## The slash trigger
Place your cursor in any text input and type `/`. A search popover appears with every available function. Type to filter, click to insert. Each function is inserted as a styled badge with empty argument slots — fill them in with text, numbers, or mentions from previous steps.
## Anatomy of a data manipulation function
Once inserted, a function looks like this in the input:
* The **function name** appears as a pill on the left.
* Arguments are separated by **semicolons (`;`)**, not commas.
* A matching pill closes the function on the right.
* A **preview panel** below the input shows the evaluated result while you edit. If the function has a type problem (e.g. passing text where a number is expected), the panel shows the error.
You can mix plain text, mentions, and functions in the same input. The function's result replaces the badge when the flow runs.
## Quoting text values
For text arguments, **quotes are optional**. The editor accepts both styles and gives you the same result:
* Without quotes: `combine(John; Smith; -)` → `John-Smith`
* With quotes: `combine("John"; "Smith"; "-")` → `John-Smith`
Use whichever feels natural. Quotes are useful when:
* The text contains a semicolon (which would otherwise be read as the next argument's separator)
* You want to be explicit about where the text starts and ends
**Empty or whitespace-only values are the one case where quotes are required.** Without quotes, the editor treats an empty slot as "no argument" and trims any whitespace, so:
* For an **empty string**, write `""` — e.g. `coalesce(""; John)` → `John`
* For a **single space** as a separator, write `" "` — e.g. `combine(John; Smith; " ")` → `John Smith`
Without quotes, `combine(John; Smith; )` would treat the third argument as missing and fall back to no separator.
## Recipes
### Combine a first and last name
`combine(first_name; " "; last_name)` → `"Sara Mitchell"`
Use `combine` whenever you need to glue several values together with a separator.
### Capitalize a customer name
`titlecase(customer_name)` → `"Sara Mitchell"`
Use `uppercase` if you want everything in caps (`"SARA MITCHELL"`), or `lowercase` for the opposite.
### Format a date for display
`format_date(order.created_at; MMM DD, YYYY)` → `"Jan 15, 2025"`
For a fully written-out date, use `format_date_long(order.created_at)` → `"Friday, January 15, 2025"`.
### Get the first item of a list
`first_item(tags)` → the first element. Use `last_item` for the last, or `item_at(tags; 2)` to pick by index.
### Use a fallback when a value is missing
`coalesce(customer.preferred_name; customer.first_name; "Friend")` → returns the first non-empty value, skipping empty ones.
Use `if_empty(value; fallback)` for a single fallback, or `if_null(value; fallback)` when the field could be `null` specifically.
### Branch on a condition
`if(order.total > 1000; "High value"; "Standard")`
The first argument is the condition. The second is what to return when it's true, the third when it's false.
### Strip whitespace and check length
`length(trim(user_input))` → tells you how many characters there are after the leading and trailing spaces are removed. Nest functions freely — the inner one runs first.
### Extract an email from a longer string
`extract_email(message_body)` → returns the first email address found in the text. Use `extract_url` for URLs.
### Round a calculated total
`round(subtotal * 1.0825; 2)` → `49.99`
The second argument is how many decimal places to keep.
### Sum a number field across a list
`sum(line_items; amount)` → adds up the `amount` field of every item in the list. Use `average` for the mean, or `max_in_list` / `min_in_list` for extremes.
### Compute days between two dates
`days_between(order.created_at; today())` → the integer day count. Combine with `if` to flag overdue records.
### Map a value through a lookup
`switch(country_code; "US"; "North America"; "DE"; "Europe"; "JP"; "Asia")` → returns `"North America"` for `"US"`. Write the pairs inline.
## Advanced tips
### Nesting functions
Any function can take another function as one of its arguments. Read them inside-out: `uppercase(trim(customer_name))` first trims, then uppercases. The hover popover on each badge shows what type each argument expects.
### Mixing static text with functions
You can drop functions anywhere inside a regular text input. Type some text, insert a function, type more text. The output is a single string with the function's result substituted in.
### Mixing mentions and functions
Mentions like `{{step.field}}` work as function arguments. Drop a mention into any argument slot and the function uses the resolved value at runtime.
### When the preview shows an error
If you see a red error message under the input, it usually means one of:
* **Wrong number of values** — you have too few or too many arguments. Check the hover popover for the expected count.
* **Type mismatch** — you passed text where a number is expected, or similar. Wrap the value in `to_number(...)` or `to_date(...)` if it needs converting.
* **Unknown function** — the function name was renamed or removed. Re-insert it with `/` to pick a current name.
The flow won't run a step whose function is in error — fix it before publishing.
## See also
* [Data Manipulation Functions](./formula-reference) — every available function, grouped by category, with signature and example
* [Passing Data](./passing-data) — using mentions to insert values from previous steps