␡
- Beneath the Abstraction
- Opening a Database
- Adding Data to the Database
- Amending Elements in a Database
- Reading from a Database
- Determining Whether an Item Exists in a Database
- Deleting an Item from a Database
- Adding Complex Data Structures to a Database
- An Example
- Summary
- Q&A
- Workshop
This chapter is from the book
This chapter is from the book
This chapter is from the book
This chapter is from the book
Determining Whether an Item Exists in a Database
Before reading or setting an element in a database, it is sometimes useful to know whether the element exists. You can do this with the dba_exists() function. dba_exists() requires the name of the element for which you are testing and a valid DBA resource. It returns true if the element exists.
if ( dba_exists("Tricorder", $dbh ) )
print dba_fetch( "Tricorder", $dbh );