Optimizing SQL Anywhere performance over a WAN

·定制PB与SQL Anywhere的程序发布
·如何在局域网上设置Sybase SQL AnyWhe
·利用VB驱动pcAnyWhere进行自动文件传
·ODBC 应用与SQL Anywhere Server或SQL
·让JavaME程序真正Run Anywhere
·Optimizing SQL Anywhere performance
·VB驱动pcAnyWhere进行文件传输

根据SQL Anywhere User's Guide所作小结。绝大部分都可用直接于Sybase数据库。

SELECT语句

SELECT *

  FROM employee

SELECT *

  FROM employee

  ORDER BY emp_lname ASC

SELECT *

  FROM employee

  ORDER BY emp_lname DESC

SELECT emp_lname, dept_id, birth_date

  FROM employee

SELECT *

  FROM employee

  WHERE emp_fname='John'

(一定使用单引号)

SELECT emp_fname, emp_lname, birth_date

  FROM employee

  WHERE emp_fname = 'John'

  ORDER BY birth_date

SELECT emp_lname, birth_date

  FROM employee

  WHERE birth_date < 'March 3, 1964'

(=、<、>、<=、>=、<>，加上AND与OR)

SELECT emp_lname, emp_fname

  FROM employee

  WHERE emp_lname LIKE 'br%'

(%、_)

SELECT emp_lname, emp_fname

  FROM employee

  WHERE SOUNDEX( emp_lname ) = SOUNDEX( 'Brown' )

(找出英文中发音相同的记录，中文下用处不大)

SELECT emp_lname, birth_date

  FROM employee

  WHERE birth_date BETWEEN '1965-1-1' AND '1965-3-31'

SELECT emp_lname, emp_id

  FROM employee

  WHERE emp_lname IN ('yeung', 'bucceri', 'charlton')

连接表

SELECT *

  FROM sales_order, employee

  WHERE sales_order.sales_rep = employee.emp_id

SELECT E.emp_lname, S.id, S.order_date

  FROM sales_order as S, employee as E

  WHERE S.sales_rep = E.emp_id

  ORDER BY E.emp_lname

连接两表的快捷键：KEY JOIN及NATURAL JOIN，最好用WHERE.

SELECT emp_lname, id, order_date

  FROM sales_order

  KEY JOIN employee

(主键与外部键对应的地方，就可以用KEY JOIN)

SELECT company_name,

  CAST( SUM(sales_order_items.quantity * product.unit_price) AS INTEGER) AS value

  FROM customer

  KEY JOIN sales_order

  KEY JOIN sales_order_items

  KEY JOIN product

  GROUP BY company_name

SELECT emp_lname, dept_name

  FROM employee

  NATURAL JOIN department

(找出两表间有相同的字段名，进行连结)

集合

SELECT count( * )

  FROM employee

SELECT　 count( * ),

  min( birth_date ),

  max( birth_date )

  FROM employee

(MIN, MAX, COUNT, AVG, SUM, LIST，作为单独的一列选出)

SELECT sales_rep, count( * )

  FROM sales_order

  GROUP BY sales_rep

(在使用GROUP BY时，对于GROUP BY指定的字段，其每一个不同的值都会组成一行)

SELECT sales_rep, count( * )

  FROM  sales_order

  KEY JOIN employee

  GROUP BY sales_rep

  HAVING count( * ) > 55

更新数据库

INSERT

  INTO department ( dept_id, dept_name, dept_head_id )

  VALUES ( 220, 'Eastern Sales', 902 )

INSERT

  INTO department

  VALUES ( 220, 'Eastern Sales', 902 )

UPDATE employee

  SET dept_id = 400, manager_id = 1576

  WHERE emp_id = 195

DELETE

  FROM employee

  WHERE termination_date IS NOT NULL

DELETE

  FROM employee

  WHERE LEFT( phone, 3 ) = '617' AND manager_id = 902

视图

CREATE VIEW emp_dept AS

  SELECT emp_fname, emp_lname, dept_name

  FROM employee

  JOIN department ON department.dept_id = employee.dept_id

SELECT *

  FROM emp_dept

(视图能自动更新状态)

DROP VIEW emp_dept

CREATE VIEW emp_dept(FirstName, LastName, Department) AS

  SELECT emp_fname, emp_lname, dept_name

  FROM employee JOIN department ON department.dept_id = employee.dept_id

(创建视图不能使用ORDEY BY，但使用视图可以使用)

SELECT LastName, dept_head_id

  FROM emp_dept, department

  WHERE emp_dept.Department = department.dept_name

(将视图与其他表进行进一步的连结)

视图权限管理

GRANT CONNECT TO M_Kelly

IDENTIFIED BY SalesHead

CREATE VIEW SalesEmployee AS

SELECT emp_id, emp_lname, emp_fname

FROM "dba".employee

WHERE dept_id = 200

GRANT SELECT ON SalesEmployee TO M_Kelly

CONNECT USER M_Kelly IDENTIFIED BY SalesHead ;

SELECT * FROM "dba".SalesEmployee

子查询

SELECT *

  FROM sales_order_items

  WHERE prod_id IN

　  ( SELECT id

　　　  FROM product

　　　  WHERE quantity < 20 )

  ORDER BY ship_date DESC

SELECT *

  FROM fin_data

  WHERE fin_data.code = ANY (  SELECT fin_code.code

　  FROM fin_code

　  WHERE type = 'revenue' )

（=ANY 相当于IN）

SELECT *

  FROM fin_data

  WHERE fin_data.code <> ALL (  SELECT fin_code.code

　  FROM fin_code

　  WHERE type = 'revenue' )

(相当于NOT IN)

SELECT　 sales_order.id, sales_order.order_date,

  ( SELECT company_name

　  FROM customer

　  WHERE customer.id = sales_order.cust_id )

  FROM　 sales_order

  WHERE order_date > '1994/01/01'

  ORDER BY order_date

(如果其他表只要求产生一个字段，就可以使用子查询来代替连接)

SELECT company_name, state,

  ( SELECT MAX( id )

　  FROM sales_order

　  WHERE sales_order.cust_id = customer.id )

  FROM customer

  WHERE state = 'WA'

根据SQL Anywhere User's Guide所作小结。绝大部分都可用直接于Sybase数据库。

SELECT语句

SELECT *

  FROM employee

SELECT *

  FROM employee

  ORDER BY emp_lname ASC

SELECT *

  FROM employee

  ORDER BY emp_lname DESC

SELECT emp_lname, dept_id, birth_date

  FROM employee

SELECT *

  FROM employee

  WHERE emp_fname='John'

(一定使用单引号)

SELECT emp_fname, emp_lname, birth_date

  FROM employee

  WHERE emp_fname = 'John'

  ORDER BY birth_date

SELECT emp_lname, birth_date

  FROM employee

  WHERE birth_date < 'March 3, 1964'

(=、<、>、<=、>=、<>，加上AND与OR)

SELECT emp_lname, emp_fname

  FROM employee

  WHERE emp_lname LIKE 'br%'

(%、_)

SELECT emp_lname, emp_fname

  FROM employee

  WHERE SOUNDEX( emp_lname ) = SOUNDEX( 'Brown' )

(找出英文中发音相同的记录，中文下用处不大)

SELECT emp_lname, birth_date

  FROM employee

  WHERE birth_date BETWEEN '1965-1-1' AND '1965-3-31'

SELECT emp_lname, emp_id

  FROM employee

  WHERE emp_lname IN ('yeung', 'bucceri', 'charlton')

连接表

SELECT *

  FROM sales_order, employee

  WHERE sales_order.sales_rep = employee.emp_id

SELECT E.emp_lname, S.id, S.order_date

  FROM sales_order as S, employee as E

  WHERE S.sales_rep = E.emp_id

  ORDER BY E.emp_lname

连接两表的快捷键：KEY JOIN及NATURAL JOIN，最好用WHERE.

SELECT emp_lname, id, order_date

  FROM sales_order

  KEY JOIN employee

(主键与外部键对应的地方，就可以用KEY JOIN)

SELECT company_name,

  CAST( SUM(sales_order_items.quantity * product.unit_price) AS INTEGER) AS value

  FROM customer

  KEY JOIN sales_order

  KEY JOIN sales_order_items

  KEY JOIN product

  GROUP BY company_name

SELECT emp_lname, dept_name

  FROM employee

  NATURAL JOIN department

(找出两表间有相同的字段名，进行连结)

集合

SELECT count( * )

  FROM employee

SELECT　 count( * ),

  min( birth_date ),

  max( birth_date )

  FROM employee

(MIN, MAX, COUNT, AVG, SUM, LIST，作为单独的一列选出)

SELECT sales_rep, count( * )

  FROM sales_order

  GROUP BY sales_rep

(在使用GROUP BY时，对于GROUP BY指定的字段，其每一个不同的值都会组成一行)

SELECT sales_rep, count( * )

  FROM  sales_order

  KEY JOIN employee

  GROUP BY sales_rep

  HAVING count( * ) > 55

更新数据库

INSERT

  INTO department ( dept_id, dept_name, dept_head_id )

  VALUES ( 220, 'Eastern Sales', 902 )

INSERT

  INTO department

  VALUES ( 220, 'Eastern Sales', 902 )

UPDATE employee

  SET dept_id = 400, manager_id = 1576

  WHERE emp_id = 195

DELETE

  FROM employee

  WHERE termination_date IS NOT NULL

DELETE

  FROM employee

  WHERE LEFT( phone, 3 ) = '617' AND manager_id = 902

视图

CREATE VIEW emp_dept AS

  SELECT emp_fname, emp_lname, dept_name

  FROM employee

  JOIN department ON department.dept_id = employee.dept_id

SELECT *

  FROM emp_dept

(视图能自动更新状态)

DROP VIEW emp_dept

CREATE VIEW emp_dept(FirstName, LastName, Department) AS

  SELECT emp_fname, emp_lname, dept_name

  FROM employee JOIN department ON department.dept_id = employee.dept_id

(创建视图不能使用ORDEY BY，但使用视图可以使用)

SELECT LastName, dept_head_id

  FROM emp_dept, department

  WHERE emp_dept.Department = department.dept_name

(将视图与其他表进行进一步的连结)

视图权限管理

GRANT CONNECT TO M_Kelly

IDENTIFIED BY SalesHead

CREATE VIEW SalesEmployee AS

SELECT emp_id, emp_lname, emp_fname

FROM "dba".employee

WHERE dept_id = 200

GRANT SELECT ON SalesEmployee TO M_Kelly

CONNECT USER M_Kelly IDENTIFIED BY SalesHead ;

SELECT * FROM "dba".SalesEmployee

子查询

SELECT *

  FROM sales_order_items

  WHERE prod_id IN

　  ( SELECT id

　　　  FROM product

　　　  WHERE quantity < 20 )

  ORDER BY ship_date DESC

SELECT *

  FROM fin_data

  WHERE fin_data.code = ANY (  SELECT fin_code.code

　  FROM fin_code

　  WHERE type = 'revenue' )

（=ANY 相当于IN）

SELECT *

  FROM fin_data

  WHERE fin_data.code <> ALL (  SELECT fin_code.code

　  FROM fin_code

　  WHERE type = 'revenue' )

(相当于NOT IN)

SELECT　 sales_order.id, sales_order.order_date,

  ( SELECT company_name

　  FROM customer

　  WHERE customer.id = sales_order.cust_id )

  FROM　 sales_order

  WHERE order_date > '1994/01/01'

  ORDER BY order_date

(如果其他表只要求产生一个字段，就可以使用子查询来代替连接)

SELECT company_name, state,

  ( SELECT MAX( id )

　  FROM sales_order

　  WHERE sales_order.cust_id = customer.id )

  FROM customer

  WHERE state = 'WA'

SELECT  company_name, MAX( sales_order.id ),state

  FROM customer

  KEY LEFT OUTER JOIN sales_order

  WHERE state = 'WA'

  GROUP BY company_name, state

系统表

SYSCATALOG，查看所有的表

SYSCOLUMNS， 查看表的字段属性

  FROM customer

  KEY LEFT OUTER JOIN sales_order

  WHERE state = 'WA'

  GROUP BY company_name, state

系统表

SYSCATALOG，查看所有的表

SYSCOLUMNS， 查看表的字段属性