![]() ![]() How to: Create Less Frequently Used Indexesĭescribes how to create indexes you use rarely or for a special task.ĭescribes how to select a controlling, or master, index for a table.ĭescribes how the user can change the display of records at run time. In This Sectionĭescribes different types of Visual FoxPro index files for storing indexes.ĭescribes different types of expresions you can use to create indexes.Ĭonsiderations for Creating Index Expressionsĭescribes considerations to remember when creating index expressions.ĭiscusses how indexes based on deleted records improve query performance and ensure use of Rushmore query optimization.ĭescribes how to add filters to indexes so you can select records containing only the data that you want. Persistent relationships between database tables are stored in the database file and exist as the default relationships when you use the tables in the data environment. You can also use indexes to create persistent relationships between tables in a database, making it possible for you to access the exact records you want. You can use different types of index files to store indexes depending on their frequency of use. You can create and store different ordering scenarios for tables by creating multiple indexes for the same table. For example, you might want to organize a customer table by contact name to quickly find the name you want or by postal code to generate mailing labels that are presorted for efficient mailing. In addition, you can create different indexes for a table so that you can change the order in which your application processes records. You can also add a filter to the index so you can add only those records that meet the filter criteria to the index.Īfter you create the table index, you can set the order of records in the table to the index so that your application processes records in the order specified. You can create a table index based on the company name field so that your application can process records in the order specified by the index you created. For example, suppose you want to process records in a customer table by company name in alphabetical order. An index does not change the physical order of the records stored in the table rather, it provides an efficient and versatile mechanism for accessing table records. You can control the order and increase the speed of processing table records by creating an index for the table. When your application performs operations on the table, the records are processed in the order they were entered. ![]() By default, Visual FoxPro stores records in the table in the order that you enter them. When you create a table, Visual FoxPro creates a table (.dbf) file and, if your table includes memo or general fields, the associated table memo (.fpt) file. ![]()
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