event 
Logical Entity Name  event 
Default Table Name  event 
Definition  Summary information on an event 

event Columns 
ColumnName  Domain  Datatype  NULL  Definition 
evid(PK)    NUMBER(15, 0)  NO  Event identifier. Each event is assigned a unique integer which identifies it in a database. It is possible for several records in the Origin relation to have the same evid. This indicates there are several opinions about the location of the event. The evid does not have to be identical to the local network’s event identifier, which is stored in the Origin table. This allows merging data for a single event from multiple sources without insisting that database evid is identical to the source’s local event identifier 
prefor(FK)    NUMBER(15, 0)  YES  Preferred origin. This attribute holds the origin identifier, orid, that points to the preferred origin for a seismic event 
prefmag(FK)    NUMBER(15, 0)  YES  Preferred magnitude. This attribute holds the magnitude identifier, magid, that points to the preferred magnitude for a seismic event or an origin 
prefmec(FK)    NUMBER(15, 0)  YES  Preferred mechanism. This attribute holds the mechanism identifier, mecid, that points to the preferred mechanism for a seismic event or an origin 
commid    NUMBER(15, 0)  YES  Comment identification. This is a key used to point to free-form comments entered in the Remark relation. These comments store additional information about a tuple in another relation. Within the Remark relation, there may be many tuples with the same commid and different lineno, but the same commid will appear in only one other tuple among the rest of the relations in the database 
auth    VARCHAR2(15)  NO  The auth field specifies the source of the information. This may be a network identifier (FDSN or otherwise), or any other string indicating the source of the information in the record 
subsource    VARCHAR2(8)  YES  A second identifier to specify the system or process that derived the data. e.g., the origin's AUTH is CI, but the subsource (the solution) was computed by JIGGLE 
etype(FK)    VARCHAR2(2)  NO  This attribute is used to identify the type of seismic event, when known 
selectflag    NUMBER(1, 0)  YES  This flag describes the “definitive” definition of an event. Helps to differentiate which event to use from two different real-time systems 
lddate    DATE  YES  Load date. Date and time that the record was created, in Oracle date datatype 
version    NUMBER(3, 0)  NO  Event version number. This attribute is incremented each time the preferred origin, magnitude or mechanism of the event is updated 

event Primary and Unique Keys 
Key Name  Key Type  Keys 
evkey01  PrimaryKey  evid 

event Foreign Keys 
Parent Relationships: 
Table Name  Type  Cardinality  Constraint Name  VerbPhrase  InversePhrase  Foreign Keys  Is Supertype  Deferrable  Initially Deferred 
eventtype  Non-Identifying  One To Zero or More        etype  NO  NO  NO 
mec  Non-Identifying  Zero or One to Zero or More  Eve_Mec      prefmec  NO  NO  NO 
netmag  Non-Identifying  Zero or One to Zero or More  Eve_Net      prefmag  NO  NO  NO 
origin  Non-Identifying  Zero or One to Zero or More  Eve_Ori      prefor  NO  NO  NO 
Child Relationships: 
Table Name  Type  Cardinality  Constraint Name  VerbPhrase  InversePhrase  Foreign Keys  Is Subtype  Deferrable  Initially Deferred 
eventprefmec  Non-Identifying  One To Zero or More          NO  NO  NO 
eventprefmag  Non-Identifying  One To Zero or More  Epm_Eve        NO  NO  NO 
origin  Non-Identifying  One To Zero or More  Ori_Eve        NO  NO  NO 

event Check Constraints 
Check Constraint Name  CheckConstraint 
event02  evid > 0