 | HDBC-MissingH API Manual | Contents | Index |
| MissingH.AnyDBM.HDBCDBM |
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HDBC backend for DBM databases
Written by John Goerzen, jgoerzen@complete.org
| data HDBCDBM |
| openSimpleHDBCDBM :: String -> Connection -> IO HDBCDBM |
| openHDBCDBM :: String -> String -> String -> Connection -> IO HDBCDBM |
Main HDBC DBM type. Please note that accessor methods on these objects will not return SqlErrors since AnyDBM users won't expect them. Instead, they will marshal those into IOErrors. Also, please note that you cannot expect a HDBCDBM to be able to store the NUL character since most SQL databases can't store it. If you need to be able to store that character with your data, I suggest passing your data through read/show around this module. | |
 Instances | |
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Opens a DBM connection to the specified table and database.
If the given table does not already exist, it will be created for you automatically.
The column names dbmkey and dbmval will be used.
The clone method will be used to obtain a new handle to the database for internal use. That will help prevent conflicts with things like commits from occuring with the main application handle. You should not have to worry about side-effects to your main application as a result of using this function.
If you need more control, see openHDBCDBM
Please note that HDBCDBM checks dbTransactionSupport. If your database indicates that transactions are NOT supported (such as MySQL), then atomicity and safety may not be guaranteed in multithreaded programs.
| :: String | Name of table to use |
| -> String | Name of column with keys |
| -> String | Name of column with values |
| -> Connection | HDBC connection object to clone |
| -> IO HDBCDBM | Returned DBM object |
Opens a DBM connection to the specified table, column name for key, column name for value, and database. It is an error if the given table does not exist, lacks the specified columns, or has an incorrect type definition for the specified columns. However, it is not guaranteed that this error will be detected at object creation time. This function does not create a table for you if it doesn't exist. You can use the table created and used by openSimpleHDBCDBM like this: openHDBCDBM "tablename" "dbmkey" "dbmval" conn Incidentally, such a table could be created with: CREATE TABLE tablename (dbmkey text NOT NULL PRIMARY KEY, dmval text NOT NULL) The clone method will be used to obtain a new handle to the database for internal use. That will help prevent conflicts with things like commits from occuring with the main application handle. You should not have to worry about side-effects to your main application as a result of using this function. | |