| More docs on the ARB website. See also index of helppages. Last update on 27. Jun 2017 .

Main topics:

- ARB: a Short Introduction
- Glossary

Related topics:

- Regular Expressions (REG)
- ARB Command Interpreter (ACI)
- Search Database for Species

# Searching

- OCCURRENCE
- DESCRIPTION
- SEARCH FIELD
- SEARCH EXPRESSION
- SORTING RESULTS
- NOTES
- EXAMPLES
- WARNINGS
- BUGS

## OCCURRENCE

### ARB_NT/Species/Search and Query

### ARB_NT/Genome/Search and Query

## DESCRIPTION

### This describes the search feature in ARB. When we talk about 'items' below, we mean e.g. 'species', 'genes', etc., depending which search tool you are currently using.

## SEARCH FIELD

### Each search expression applies either

- to a specific item field (e.g. 'full_name') or
- if you select the '[any field]' pseudo search field, all direct database subentries of the item are searched for the expression. This does NOT work for subcontainers (i.e. 'ali16s/data' is not searched).

## SEARCH EXPRESSION

- Each expression tries to match the complete field content, i.e. searching for 'test' will match only fields which exactly contain 'test' (not 'my test' or 'testing').
- If you search for '' (empty expression), all fields w/o data, i.e. all non-existing fields will be found.
- if you want to match all fields that contain some substring then use wildcards:
  - '*'
    will match any number of characters (including no characters).
  - '?'
    will match exactly one character
  If the whole search expression is '*', then it is handled like '?*' (which means 'at least one character'). So searching for '*' will report all existing fields.
  Examples:

      '*pseu*'        matches all fields with the substring 'pseu'
      'pyrococcus*'   matches all fields starting with 'pyrococcus'
      '*bact*ther*'   matches all fields with the substring 'bact' followed by 'ther'
                      (there may be many characters in-between or none, i.e. it as
                      well matches 'bactther')

- if the first character is '<' or '>' and the rest is a number, then a numerical comparison is done:
  - '<7'
    matches all fields containing a number smaller than 7
  - '>10'
    matches all fields containing a number greater than 10
  Be careful:
  Negating '<7' does NOT only match numbers greater or equal to seven. It as well finds all non-numeric contents. Use something like '>6.999' instead.
- if the first character is '/' then the following regular expression is used for the query (see ´Regular Expressions (REG)´).
- if the first character is '|' then the following ACI expression is evaluated and the query hits, if the evaluation is not "0". See ´ARB Command Interpreter (ACI)´.
- if the query string is completely empty, it hits if the selected field does not exist.

## SORTING RESULTS

### Search results are displayed unsorted by default. You can sort them, by selecting a different order with the sort radio button. The available sort criteria are

    unsorted       display items like they are stored in database
    by value       sort by content of first query field
    by id          sort by unique item id (e.g. 'name' for species)
    by parent      sort by globally unique id of parent item (e.g. 'name' of organism for genes)
    by marked      sort marked before unmarked items
    by hit         sort by (and display) hit description (the hit description tells you
                   why an item was hit by query)
    reverse        reverts previously selected sort order

### ARB remembers and uses all the sort criteria you apply.

### Example: Selecting 'by id' will sort the items by their id (e.g. 'name'). If you select 'by value' afterwards, ARB will sort items by the content of the first query field - if the contents of some items are equal, it will still sort them by name.

## NOTES

### Wildcarded or exact search always searches case insensitive. Regular expression search always searches case sensitive.

## EXAMPLES

### see ´Search Database for Species´

## WARNINGS

### Using ACI is a bit tricky here, cause you cannot see what happens. Using 'trace(1)' somewhere in the ACI expression starts to print an ACI trace to the console. Don't forget to use 'trace(0)' afterwards, otherwise that may slow down ARB.

## BUGS

### No bugs known