Database Library Documentation¶
db.entry ()
Creates a DBENTRY pointer which can be used with all implemented static database
access functions. dbFreeEntry will be called on the pointer automatically when the
entry is garbage collected.
Static Database Access¶
The following list of static database access functions are implemented, largely unchanged from their C API. Naming conventions have been changed to drop the initial “db” prefix and for the next character to be lowercase; so, for example, dbGetFieldName would become the module function getFieldName.
Functions which would return a status code, like dbFindRecord, will instead return a boolean representing success or failure (true or false respectively). Where a DBENTRY pointer is required as a parameter, instead instances of the dbentry class will be used, created with the aforementioned db.entry function.
- getNRecordTypes
- findRecordType
- firstRecordType
- nextRecordType
- getRecordTypeName
- getNFields
- firstField
- nextField
- getFieldDbfType
- getFieldName
- getDefault
- getPrompt
- getPromptGroup
- putRecordAttribute
- getRecordAttribute
- getNAliases
- getNRecords
- findRecord
- firstRecord
- nextRecord
- getRecordName
- isAlias
- createRecord
- createAlias
- deleteRecord
- deleteAliases
- copyRecord
- findField
- foundField
- getString
- putString
- isDefaultValue
- getNMenuChoices
- getMenuIndex
- putMenuIndex
- getMenuStringFromIndex
- getMenuIndexFromString
- getNLinks
- getLinkField
- firstInfo
- nextInfo
- findInfo
- getInfoName
- getInfoString
- putInfoString
- putInfo
- deleteInfo
- getInfo
db.registerDatabaseHook (dbhook)
Registers the provided function so that it is invoked each time the dbLoadRecords
function is called by the IOC. The callback hook is invoked with two parameters;
the first being the filepath to the database file being loaded, and the other
being a table of the macro definitions provided to dbLoadRecords.
dbhook [function] - The callback function to be invoked
db.record ([recordtype,] recordname)
Creates an instance of the dbrecord class, a wrapper around record creation/access.
recordtype [string] - The typename of the record (ai, mbbo, calc, etc) Optional.
If the typename is left out, constructor will operate only
to find a record, not create one.
recordname [string] - The name of the record. If the name already exists, the
returned instance will refer to the existing record. If
there is no record by that name, the constructor will
create one.
Returns a class instance with four instance methods, name, type, field, and info.
'name' and 'type' are accessor methods that will return the record name and the
RTYP of the record.
'field' and 'info' are both functions that take in two strings as parameters, the
first being a name and the second a value. 'field' attempts to find the record
field with the given name and then calls dbPutString to set the value. While 'info'
calls dbPutInfo to add a new info field with the given name and value to the record.
rec = db.record("stringin", "x:y:z")
rec:field("VAL", "test")
rec:info("autosave", "VAL")
The class instance itself can also be called as a function, taking in a dictionary
of name-vale pairs. In doing so, the 'field' function is called for each pair,
passing through the names and values to the function.
With lua syntactical sugar, you can chain together the record creation and the
setting of fields like so:
db.record("ai", "x:y:z") {
DTYP = "asynInt32",
INP = "@asyn(A_PORT,0,1)PARAM_NAME"
}
db.list ()
Returns a list of all the PVs currently defined in the IOC. Each element of the
list is a db.record instance.