lookup: what changed
Revision 0 to 1. Removed lines have a minus sign; added lines have a plus sign.
Title: lookup
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| 1 | + | ## Definition | |
| 2 | + | ||
| 3 | + | Unit: FreePascal, unit **db** | |
| 4 | + | ||
| 5 | + | ``` pascal | |
| 6 | + | function Lookup(const KeyFields: string; const KeyValues: Variant; const ResultFields: string): Variant; | |
| 7 | + | ``` | |
| 8 | + | ||
| 9 | + | Official documentation: none | |
| 10 | + | ||
| 11 | + | ## Description | |
| 12 | + | ||
| 13 | + | **lookup** is similar to [[locate]] in that it looks for a record in the dataset where the specified search values for the specified fields match. | |
| 14 | + | ||
| 15 | + | If found, the function returns a variant array with the values of the ResultFields (a semicolon-delimited list of desired fields). If not found, it returns **Null**. In neither case does it change the current physical record/cursor. | |
| 16 | + | ||
| 17 | + | KeyFields can be a single field name or a semicolon-separated list of fields. | |
| 18 | + | ||
| 19 | + | KeyValue can be a variant or a variant array and the number of items must match the number of fields specified in KeyFields. | |
| 20 | + | ||
| 21 | + | > **Note:** Lookup is only implemented in non-unidirectional datasets, i.e. you must be able to move back and forwards through the dataset. | |
| 22 | + | ||
| 23 | + | ## See also | |
| 24 | + | ||
| 25 | + | - [[locate]] | |
| 26 | + | - [Description of how to use lookup with Delphi](http://delphi.about.com/od/database/l/aa052901a.htm) | |
| 27 | + | ||
| 28 | + | --- | |
| 29 | + | *From the Free Pascal wiki, page "lookup", as it stood on 2020-02-19 after a change by Trev, out of the wiki's dump of 2024-05-26. Copyright stays with the author who wrote it, according to the old wiki's [[Licensing]] page. If you have concerns about this material, [message the admin](/wiki-contact).* |