日期字段将自动填写

Question

我使用PostgreSQL和创建见下表：

CREATE TABLE "TrainingMatrix" 
(
    payroll text NOT NULL, 
    "TrainingName" text NOT NULL, 
    "Institute" text, 
    "TrainingDate" date NOT NULL, 
    "ExpiryDate" date, 
    "RecorderName" text, 
    "EnteringDate" date, 
    CONSTRAINT "TrainingMatrix_pkey" PRIMARY KEY (payroll, "TrainingName", "TrainingDate") 
) 

我想让EnteringDate被自动由当前的日期在机器每次进入记录填写。

Answer 1

CREATE TABLE "TrainingMatrix" 
(
    payroll text NOT NULL, 
    "TrainingName" text NOT NULL, 
    "Institute" text, 
    "TrainingDate" date NOT NULL, 
    "ExpiryDate" date, 
    "RecorderName" text, 
    "EnteringDate" date NOT NULL default current_date,--"EnteringDate" date, 
    CONSTRAINT "TrainingMatrix_pkey" PRIMARY KEY (payroll, "TrainingName", "TrainingDate") 
) 

Answer 2

使用默认的关键字

column datatype default sysdate 

检查这个问题，以及

How to set default value for column of new created table from select statement in 11g

Answer 3

通过使用默认的系统日期，你可以achive所需的输出。

CREATE TABLE "TrainingMatrix" 
(
    payroll text NOT NULL, 
    "TrainingName" text NOT NULL, 
    "Institute" text, 
    "TrainingDate" date NOT NULL, 
    "ExpiryDate" date, 
    "RecorderName" text, 
    "EnteringDate" date default sysdate, 
    CONSTRAINT "TrainingMatrix_pkey" PRIMARY KEY (payroll, "TrainingName", "TrainingDate") 
) 

Answer 4

CREATE TABLE "TrainingMatrix" 
(
    payroll text NOT NULL, 
    "TrainingName" text NOT NULL, 
    "Institute" text, 
    "TrainingDate" date NOT NULL, 
    "ExpiryDate" date, 
    "RecorderName" text, 
    "EnteringDate" date not null default current_timestamp, 
    CONSTRAINT "TrainingMatrix_pkey" PRIMARY KEY (payroll, "TrainingName", "TrainingDate") 
) 

CURRENT_TIMESTAMP是equivelent到现在（）将给当前日期&时间（包括时区）http://www.postgresql.org/docs/8.1/static/functions-datetime.html

定义列不空也将有助于确保没有记录明确地进入没有时间戳。