1. A method executed by at least one processor in a database system, comprising: providing a map that correlates expressions including at least one condition on at least one attribute in a table to corresponding characters; mapping, using the map by the at least one processor, table rows of the table to corresponding ones of the characters, wherein the mapping produces a string of the characters, wherein the mapping comprises evaluating the expressions against values of the at least one attribute in corresponding ones of the table rows of the table, identifying respective ones of the characters according to the evaluating, and adding the identified characters to the string; receiving, by the at least one processor, a query to identify a pattern in the table rows; and accessing, by the at least one processor, the string of the characters to process the query, wherein processing the query comprises performing a string search in the string of characters, rather than a search in the table, to identify the pattern.