Searching for symbols and emojis

This topic describes how to make symbols and emojis searchable in a dtSearch index and how to use regular expressions to search for certain symbols reserved as search operators, such as the % sign.

Searching for symbols

There are two ways to make a character searchable, depending on whether the hexadecimal character code is less than 007F or greater than 0080.

Also refer to the Symbols quick reference guide. For more information, log into the Relativity Community to access the dtSearch Unicode values for Special Characters article.

For hexadecimal characters less than 007F

To search for symbols with hexadecimal characters less than 007F, perform the following steps:

1. Create a dtSearch index.
2. Update the alphabet file to include the % sign as an indexed character:
   1. Enter the following under [Letters] // Original letter, lower case, upper case, unaccented:
      [Space] [%] [Space] [%] [Space] [%] [Space] [%]
      Note: You must have a leading space. You cannot have a trailing space.
      
   2. Delete the % sign from the [Ignore] section. Take care not to remove the gray boxes, which represent non-printable characters. Removing them may break the index.
      Before:
      
      After:
      
   3. Repeat these steps for any other symbols that you need to make indexed. Delete the appropriate symbols from the [Spaces], [Ignore], or [Hyphens] sections. Please note, if you edit the hyphen, space, or ignore section, you will need to also keep the leading space. Removal of leading spaces will cause errors in Relativity.
3. Perform a full build of the dtSearch index.

You can search for terms containing the % sign using a regular expression. For example, if you need to search for documents that contain the term 75%, you would enter the following in your search box, ensuring you select the proper dtSearch index:

"##75\u0025"

To break this regular expression down:

• ## signals to Relativity to treat the string as a regular expression.
• \u indicates a search using a character's Unicode value, to follow in the next four characters.
  
  Note: Remove the "\u" before the four character value in the Unicode Entity field when adding to your Alphabet file.
• 0025 indicates the hexadecimal Unicode value for the % sign.

Note: For most symbols, once you have indexed the character in the alphabet file, you can type them directly into the dtSearch box without using regular expressions. For example, to search for 30!, enter 30! into the dtSearch box after you have made ! an indexed character. You only need to use RegEx for certain symbols.

Another example would be searching for documents that contain the term 75 %, you would enter the following in your search box, ensuring you select the proper dtSearch index.

"##75" w/1 "##\u0025"

• ## signals to Relativity to treat the string as a regular expression.
• w/1 indicates that the number be within the % sign.
• \u indicates a search using a character's Unicode value, to follow in the next four characters.
• 0025 indicates the hexadecimal Unicode value for the % sign.

For hexadecimal characters greater than 0080

For characters outside of the ASCII code range, characters greater than 0080 such as § and £, you cannot make them searchable by adding them to the letters section. Instead, create an AdditionalLetters section at the bottom of the alphabet file and insert the characters' Unicode value. For example: AdditionalLetters = 20AC 00A3 00A5.Then perform a full build of the dtSearch index.

This would make the Euro symbol, British Pound, and Japanese Yen searchable.

Note: Be sure to remove the "\u" before the four character value in the Unicode Entity field when adding to your Alphabet file.