title: Create Default Constraint in Oracle SQL
body: <p>Coming from SQL Server, I am learning some Oracle syntax.</p>
  
  <p>This is my table DDL</p>
  
  <pre><code>CREATE TABLE "CDR"."EXTDL_REPORTSETS"
    (
      "ID"                NUMBER(38,0) NOT NULL ENABLE,
      "SHORTNAME"         NUMBER(38,0) NOT NULL ENABLE,
      "DESCRIPTION"       NUMBER(38,0) NOT NULL ENABLE,
      "ASOFSTARTDATETIME" NUMBER(38,0) NOT NULL ENABLE,
      "ASOFENDDATETIME"   NUMBER(38,0) NOT NULL ENABLE,
      CONSTRAINT "PK_EXTDL_REPORTSETS" PRIMARY KEY ("ID") USING INDEX PCTFREE 10 INITRANS 2 MAXTRANS 255 STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645 PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT) TABLESPACE "CDR_DATA" ENABLE
    )
    PCTFREE 10 PCTUSED 40 INITRANS 1 MAXTRANS 255 NOCOMPRESS LOGGING STORAGE
    (
      INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645 PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT
    )
    TABLESPACE "CDR_DATA" ;
  </code></pre>
  
  <p>I want to default ASOFSTARTDATETIME to SysDate. How do I set a default constraint in PL/SQL?</p>
  
  <p><strong>EDIT</strong></p>
  
  <p>The datatypes had gotten messed up, so I corrected it.</p>
  
  <pre><code>CREATE TABLE CDR.ExtDL_Reportsets(
      Id                   NUMBER(38, 0)    NOT NULL,
      ShortName            VARCHAR2(255)    NOT NULL,
      Description          VARCHAR2(500)    NOT NULL,
      AsOfStartDateTime    DATE             NOT NULL,
      AsOfEndDateTime      DATE,
      CONSTRAINT PK_ExtDL_Reportsets PRIMARY KEY (Id)
  )
  ;
  </code></pre>