Using Wildcard Pattern Matching in Queries

The LIMS’ query-by-example (QBE) controls provide a powerful method to retrieve sample data for viewing, editing or report generation. The QBE controls appear throughout the system wherever sample querying is supported. The “Additional” tab of the query controls includes several QBE controls used to query data in sample text fields such as Sample ID, Description Notes,Conclusions, and Customer Sample ID.

These controls support partial string searches using wildcard pattern matching. Pattern matching uses special wildcard characters as placeholders for other characters to find values when you either know only part of the value you want to find or you want to find values that start or end with specific characters or match a specific pattern.

QBE controls that support wildcard pattern matching normally indicate the feature is available when you hold the mouse over the control (see the figure, below).

Double-clicking within a QBE control that supports pattern matching will normally display a popup showing the wildcard characters (see below). Pattern matching is available in most controls used to enter alphanumeric text. That is, QBE controls other than pick lists, check boxes, and those used to enter dates, times and numbers only will typically support pattern matching. If you have a Full System license with added custom text fields, pattern matching will also be available in these fields on the “Custom” tab of the query controls.

The table below shows the available wildcard characters and examples of their use.

Note that you can use any combination of the wildcard characters to create your own partial string searches. The table below provides additional examples.

Although queries using wildcard pattern matching will not be particularly fast with some fields in large databases, they are often very useful when searching for specific data. If you have a full copy of Microsoft Access, you can learn more about pattern matching by searching for “wildcard” in the Help system’s index.