OPEN SQL:插入、删除、修改语法

1. UPDATE 用于实现对数据据的更新操作，语法如下：

UPDATE <dbtab> set f1...fn (where <condition>).

UPDATE <dbtab> FROM TABLE <itab> (where <condition>).

UPDATE 表名称 SET 列名称 = 新值 WHERE 列名称 = 某值。

例如1：更新某一行中的一个列

LastName	FirstName	Address	City
Gates	Bill	Xuanwumen 10	Beijing
Wilson		Champs-Elysees

我们为lastname是Wilson的人添加firstname:

UPDATE PERSON SET FIRSTNAME = 'Fred'
WHERE LASTNAME = 'Wilson'

结果：

LastName	FirstName	Address	City
Gates	Bill	Xuanwumen 10	Beijing
Wilson	Fred	Champs-Elysees

例如2：更新某一行中的若干列

如上，我们要修改地址（address）,并添加城市名称（city）:

UPDATE PERSON SET ADDRESS = 'Zhongshan 23'
CITY = 'Nanjing'
WHERE LASTNAME = 'Wilson'.

结果：

LastName	FirstName	Address	City
Gates	Bill	Xuanwumen 10	Beijing
Wilson	Fred	Zhongshan 23	Nanjing

例如3：

UPDATE SCUSTOM SET:DISCOUNT = '003',
TELEPHONE = '0592-123456'
WHERE ID = '456789'.

2.INSERT 用于实现对数据的新增，其语法结构如下：

INSERT INTO <dbtab> VALUES <condition>.

INSERT <dbtab> FROM TABLE <itab>.

INSERT INTO 表名称 VALUES （值1,值2,...） "指插入新的行

INSERT INTO table_name(列1,例2,...) VALUES (值1,值2,...) "指在指定的列中插入数据

例如1：在这一行下插入新的行lastname = gates的值

LastName	FirstName	Address	City
Carter	Thomas	Changan Street	Beijing

INSERT INTO PERSONS VALUES ( 'Gates', 'Bill', 'Xuanwumen 10', 'Beijing' )

结果：

LastName	FirstName	Address	City
Carter	Thomas	Changan Street	Beijing
Gates	Bill	Xuanwumen 10	Beijing

例如2.在指定列中插入数据

LastName	FirstName	Address	City
Carter	Thomas	Changan Street	Beijing
Gates	Bill	Xuanwumen 10	Beijing

INSERT INTO Persons (LastName, Address) VALUES ('Wilson', 'Champs-Elysees')

结果：

LastName	FirstName	Address	City
Carter	Thomas	Changan Street	Beijing
Gates	Bill	Xuanwumen 10	Beijing
Wilson		Champs-Elysees

例3.

TABLES SCUSTOM.
SCUSTOM-ID = '11279'.
SCUSTOM-NAME = 'JACK BLOGS'.
SCUSTOM-POSTCODE = '658896'.
SCUSTOM-CITY = 'SIGAPO'.
INSERT INTO SCUSTOM VALUES SCUSTOM. "从某一结构体获取新增数据

TABLES SAIRPORT.
SAIRPORT-ID = 'KIT'.
SAIRPORT-NAME = 'NEW ZLAND'.
INSERT SAIRPORT. "直接对表HEADER LINE赋值新增

3. DELETE 用于删除表中的数据，其语法结构如下：

DELETE FROM dbtab WHERE cond.

DELETE dbtab.

DELETE dbtab FROM TABLE itab.

TABLES SBOOK.
DELETE FROM SBOOK WHERE CARRID = 'LH'

AND CONNID = '0400'

AND FLDATE = '19950228'."按赋值条件删除透明表数据

TABLES SBOOK.
SBIIK-CARRID = 'LH'.
SBOOK-CONNID = '0400'.
SBOOK-FLDATE = '19950228'.
SBOOK-BOOKID = '00000003'.
DELETE SBOOK."按结构体条件删除表数据，按内表数据进行删除基本类似

4.MODIFY 用于修改表中的数据

当修改条件符合时，直接按条件更新表数据，若改数据不存在，则在数据表中新增一条，通过MODIFY修改或新增数据的执行效率，此使用UPDATE和INSERT效率你，其语法如下：

MODIFY dbtab.

MODIFY dbtab FROM TABLE itab.

TABLES SCUSTOM.
SCUSTOM-ID = '186999868'.
SCUSTOM-NAME = 'DAYRON ROBLES'.
SCUSTOM-POSTCODE = '39866'.
SCUSTOM-CITY = 'CUBA'.
MODIFY SCUSTOM."该表以ID为主键，此时数据库中没有符合ID='186999868'的数据，故先插入一条.

TABLES SCUSTOM.
SCUSTOM-ID = '186999868'.
SCUSTOM-NAME = 'DAYRON ROBLES'.
SCUSTOM-POSTCODE = '39866'.
SCUSTOM-CITY = 'CUBA'.
MODIFY SCUSTOM. "此时数据库中存在ID='186999868'的数据，故将其更新。

巴特西

OPEN SQL:插入、删除、修改语法

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