Oracle® Spatial
User’s Guide and Reference
10g Release 2 (10.2)
非常好的Oracle10g Spatial(10.2)的指南和参考文?br /> 英文?br />
目录?部分20多个章节Q这里只节选了W二章节的目?br /> 2 Spatial Data Types and Metadata
2.1 Simple Example: Inserting, Indexing, and Querying Spatial Data..... 2-1
2.2 SDO_GEOMETRY Object Type ...... 2-5
2.2.1 SDO_GTYPE.......... 2-5
2.2.2 SDO_SRID.......... 2-7
2.2.3 SDO_POINT .......... 2-7
2.2.4 SDO_ELEM_INFO......... 2-7
2.2.5 SDO_ORDINATES ........ 2-10
2.2.6 Usage Considerations ......... 2-11
2.3 SDO_GEOMETRY Methods......... 2-11
2.4 SDO_GEOMETRY Constructors........ 2-13
2.5 Geometry Examples........ 2-14
2.5.1 Rectangle......... 2-14
2.5.2 Polygon with a Hole......... 2-15
2.5.3 Compound Line String ....... 2-17
2.5.4 Compound Polygon ......... 2-19
2.5.5 Point........... 2-20
2.5.6 Oriented Point .......... 2-21
2.5.7 Type 0 (Zero) Element......... 2-23
2.5.8 Several Geometry Types........ 2-25
2.6 Geometry Metadata Views ........ 2-29
2.6.1 TABLE_NAME......... 2-30
2.6.2 COLUMN_NAME......... 2-30
2.6.3 DIMINFO........ 2-30
2.6.4 SRID........... 2-31
2.7 Spatial Index-Related Structures ....... 2-31
2.7.1 Spatial Index Views ....... 2-31
2.7.1.1 xxx_SDO_INDEX_INFO Views....... 2-31
2.7.1.2 xxx_SDO_INDEX_METADATA Views..... 2-32
2.7.2 Spatial Index Table Definition ....... 2-34
2.7.3 R-Tree Index Sequence Object ....... 2-35
2.8 Unit of Measurement Support ........ 2-35
直接下蝲demo文g卛_
下蝲地址:http://www.fruitres.cn/servlet/buyproductservlet?tag=single&tag1=info&PRODUCT_ID=1500381985&number=0
更多下蝲:http://www.fruitres.cn
]]>
该文档非常好的Oraclel护学习文档
文档目录如下
监控SQL
常用LSQL
查询表结?br /> 表空间用状?br /> 查询某个模式下面数据不ؓI的?br /> 客户端主Z?br /> 安装Oracle以后Q经怋用的修改表空间的SQL代码
查看回滚D名U及大小
PL/SQL入门教程
在from后面使用变量
Oracle常用数据字典
在Oracle中实现数据库的复?br /> SQL*PLUS环境输入'&字符'的方?br /> 说创建用?br /> 说Oracle启动及关闭数据库实例
说Oracle数据库导?exp)/导入(imp)
实例:Oracle导出Excel文g
实例:Oracle导出HTM文g
查看数据库保留字
数据字典及某些字D|?br />
下蝲地址 http://www.fruitres.cn/servlet/buyproductservlet?tag=single&tag1=info&PRODUCT_ID=244294537&number=0
更多资料 http://www.fruitres.cn/
]]>
1.0.4
增加了导发器、存储过E、函数的功能Qƈ且修改了不能导出KEYS全部cd的BUG
1.0.3
增加了导出Sequences、View的功能，q且导出界面默认导出到安装文件夹中的export目录?br />
1.0.2
增加了导出KEYS、INDEX的功?br />
1.0.1
增加了导出完毕以后直接点L开文g夏V打开文g的查看方式，q且支持Linux/Win q_
1.0.0
导出为html文gQ导出完毕后直接查看index.html文g卛_。导出的内容包括各个表的名称索引和注释以及表中各个字D늚明细和注?
下蝲地址 http://www.fruitres.cn/servlet/buyproductservlet?tag=single&tag1=info&PRODUCT_ID=942025602&number=0 下蝲版本1.0.4
更多工具和文档请?http://www.fruitres.cn/
]]>
I间数据库Oracle Spatial的徏立过E如下：
-- 创徏最基本的个人兴点表结?br />drop table poi;
create table poi (gid INTEGER,
opid INTEGER,
gname VARCHAR2(256),
gshape MDSYS.SDO_GEOMETRY);
-- 更新用户I间数据对象视图(建立索引依赖?
delete from USER_SDO_GEOM_METADATA where TABLE_NAME='POI' and COLUMN_NAME='GSHAPE';
insert into USER_SDO_GEOM_METADATA values ('poi',
'gshape',
MDSYS.SDO_DIM_ARRAY(MDSYS.SDO_DIM_ELEMENT('lon', -- lontitude
-64800000, -- min(china 26430867 73.41907434101486)
64800000, -- max(china 49679991 137.99997381765377)
1), -- scale (china abs 23249124)
MDSYS.SDO_DIM_ELEMENT('lat', -- latitude
-32400000, -- min(china -1677502 -4.6597267116858045)
32400000, -- max(china 21571819 59.92171939467364)
1)), -- scale (china abs 23249321)
NULL);
-- 插入一个个人兴点的SQL语句Q用标准点地物I间数据cd
delete from POI;
insert into POI values (20010001,
1,
'我的?,
MDSYS.SDO_GEOMETRY(2001, -- SDO_GTYPE
NULL, -- SDO_SRID
SDO_POINT_TYPE(41884696, 14377039, NULL), NULL, NULL));
-- 插入一个个人兴点的SQL语句Q用另一U点地物I间数据l织l构
delete from POI;
insert into POI values (20010001,
1,
'我的?,
MDSYS.SDO_GEOMETRY(2001, -- SDO_GTYPE
NULL, -- SDO_SRID
NULL, -- SDO_POINT
MDSYS.SDO_ELEM_INFO_ARRAY (1, -- SDO_STARTING_OFFSET
1, -- SDO_ETYPE
1), -- SDO_INTERPRETATION
MDSYS.SDO_ORDINATE_ARRAY (41884696,14377039)));
-- 创徏~省的R-treeI间索引
drop index POI_IDX;
CREATE INDEX POI_IDX on poi(gshape)
INDEXTYPE is MDSYS.SPATIAL_INDEX;
-- PARAMETERS('SDO_LEVEL=10000'); -- 180*60*60*1000*2/100/100*90*60*60*1000*2/100/100 = 8398080000
-- 索引_o矩ŞH口选择SQL语句(对于点地物对象，索引_o的结果是_?
SELECT * FROM POI P
WHERE sdo_filter(P.gshape,
mdsys.sdo_geometry(2003,NULL,NULL,
mdsys.sdo_elem_info_array(1,1003,3),
mdsys.sdo_ordinate_array(41883696,14376039, 41885696,14378039)),
'querytype=window') = 'TRUE';
-- _匚w矩ŞH口选择SQL语句(计算非常耗时)
SELECT * FROM POI P
WHERE sdo_relate(P.gshape,
mdsys.sdo_geometry(2003,NULL,NULL,
mdsys.sdo_elem_info_array(1,1003,3),
mdsys.sdo_ordinate_array(41883696,14376039, 41885696,14378039)),
'mask=INSIDE querytype=window') = 'TRUE';
]]>
Oracle的空间数据库的操作驱动更CQ新的驱动适用于Oracle8.0或以上，新驱动在Ҏ据库的操作上面和原有的驱动差别比较大Q不q有一点：使用变得单了
建立I间数据库和建立I间索引的步骤就略过了，那些|上有很多例子，而且实现方式上面也没有变化，下面列出查询I间数据库记录的代码Q?br />
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import oracle.spatial.geometry.JGeometry;
import java.sql.PreparedStatement;
import oracle.sql.STRUCT;
import java.sql.Connection;
/**
* <p>Title: </p>
*
* <p>Description: </p>
*
* <p>Copyright: Copyright (c) 2006</p>
*
* <p>Company: </p>
*
* @author sunfruit
* @version 1.0
*/
public class SdoSelect {
public SdoSelect() {
}
public static void main(String[] args) {
String driver = "oracle.jdbc.driver.OracleDriver";
String url = "jdbc:oracle:thin:@172.16.75.200:1521:starmap";
String uid = "hmbst";
String psw = "hmbst";
Connection conn = null;
PreparedStatement ps=null;
try {
Class.forName(driver);
conn = DriverManager.getConnection(url, uid, psw);
JGeometry jGeometry=new JGeometry(41884696,14377039,42884696,14477039,0);
STRUCT obj =jGeometry.store(jGeometry,conn);
String sql = "SELECT * FROM POISDO p WHERE sdo_filter(p.gshape,?,'querytype=window')='TRUE'";
ps = conn.prepareStatement(sql,ResultSet.TYPE_FORWARD_ONLY, ResultSet.CONCUR_READ_ONLY);
ps.clearParameters();
ps.setObject(1, obj);
// 插入点地物记?br /> ResultSet rs=ps.executeQuery();
while(rs.next())
{
STRUCT st = (oracle.sql.STRUCT)rs.getObject("gshape");
JGeometry j_geom = JGeometry.load(st);
double[] dou=j_geom.getPoint();
String buff="";
for(int i=0;i<dou.length;i++)
{
buff=buff+String.valueOf((int)dou[i])+" ";
}
System.out.println(buff);
}
}
catch (Exception ex) {
ex.printStackTrace();
}
finally
{
if(conn!=null)
{
try {
conn.close();
}
catch (SQLException ex) {
ex.printStackTrace();
}
}
if(ps!=null)
{
try {
ps.close();
}
catch (SQLException ex) {
ex.printStackTrace();
}
}
}
}
}
表POISDO的结构如?br />create table poi (
id INTEGER,
gname VARCHAR2(256),
gshape MDSYS.SDO_GEOMETRY);
]]>
Oracle的空间数据库的操作驱动更CQ新的驱动适用于Oracle8.0或以上，新驱动在Ҏ据库的操作上面和原有的驱动差别比较大Q不q有一点：使用变得单了
建立I间数据库和建立I间索引的步骤就略过了，那些|上有很多例子，而且实现方式上面也没有变化，下面列出d一条空间数据库记录的代码：
import java.sql.*;
import oracle.sql.*;
import oracle.spatial.geometry.JGeometry;
/**
* <p>Title: </p>
*
* <p>Description: </p>
*
* <p>Copyright: Copyright (c) 2006</p>
*
* <p>Company: </p>
*
* @author not attributable
* @version 1.0
*/
public class SdoAdd {
public static void main(String[] args) {
String driver = "oracle.jdbc.driver.OracleDriver";
String url = "jdbc:oracle:thin:@172.16.75.200:1521:starmap";
String uid = "hmbst";
String psw = "hmbst";
Connection conn = null;
PreparedStatement ps=null;
try {
Class.forName(driver);
conn = DriverManager.getConnection(url, uid, psw);
JGeometry jGeometry=new JGeometry(41884696,14377039,0);
STRUCT obj =jGeometry.store(jGeometry,conn);
String sql =
"insert into POISDO values(seq_poi_id.nextval,?,?)";
ps = conn.prepareStatement(sql,ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_UPDATABLE);
ps.clearParameters();
ps.setString(1, "我的?);
ps.setObject(2, obj);
// 插入点地物记?br /> ps.executeUpdate();
conn.commit();
}
catch (Exception ex) {
ex.printStackTrace();
}
finally
{
if(conn!=null)
{
try {
conn.close();
}
catch (SQLException ex) {
ex.printStackTrace();
}
}
if(ps!=null)
{
try {
ps.close();
}
catch (SQLException ex) {
ex.printStackTrace();
}
}
}
}
}
表POISDO的结构如?br />create table poi (
id INTEGER,
gname VARCHAR2(256),
gshape MDSYS.SDO_GEOMETRY);
]]>
CREATE TABLE mylake (
feature_id NUMBER PRIMARY KEY,
name VARCHAR2(32),
shape MDSYS.SDO_GEOMETRY);
Step2. ?font color="#003366">user_sdo_geom_metadata
表中插入新记录，用于描述I间字段
INSERT INTO user_sdo_geom_metadata VALUES (
'mylake', //---表名
'shape', //---字段?br /> MDSYS.SDO_DIM_ARRAY(
MDSYS.SDO_DIM_ELEMENT('X', 0, 100, 0.05), //---Xl最，最大值和容忍度?br /> MDSYS.SDO_DIM_ELEMENT('Y', 0, 100, 0.05) //---Yl最，最大值和容忍?br /> ),
NULL //---坐标p，~省为笛卡尔坐标p?/font>
);
Step3. 创徏I间索引
CREATE INDEX mylake_idx ON mylake(shape)
INDEXTYPE IS MDSYS.SPATIAL_INDEX
Step4. 插入I间数据
Oracle Spatial?code>MDSYS.SDO_GEOMETRY来存储空间数?定义为：CREATE TYPE sdo_geometry AS OBJECT (
SDO_GTYPE NUMBER,
SDO_SRID NUMBER,
SDO_POINT SDO_POINT_TYPE,
SDO_ELEM_INFO MDSYS.SDO_ELEM_INFO_ARRAY,
SDO_ORDINATES MDSYS.SDO_ORDINATE_ARRAY);
SDO_GTYPEQ?font color="#000000">用四个数字定义了所有的形状
W一?l数
W二?U性表C。用?Q?l数据，二维?
最后两?Value Geometry Description 00 UNKNOWN_GEOMETRYSpatial ignores this value 01 POINTA single point element 02 LINE or CURVEContains one line string element that may be linear, curved or both 03 POLYGONContains one polygon element with or without other polygon elements in it 04 COLLECTIONA heterogeneous collection of elements 05 MULTIPOINTContains one or more points 06 MULTILINE or MULTICURVEContains one or more line string elements 07 MULTIPOLYGONContains multiple polygon elements that maybe disjoint
SDO_SRIDQ?font color="#000000">坐标p，NULL为笛卡尔坐标pR?br />SDO_POINTQ?/font>Oracle Spatial也可定义单个的点Q?font color="#003366">SDO_POINT的定? CREATE TYPE sdo_point_type AS OBJECT (X NUMBER,Y NUMBER,Z NUMBER);
如何是二l_Z为NULL?br />SDO_ELEM_INFOQ?/font>每三个值描qC?font color="#000000">元素?br /> W一个|W一个顶点在SDO_ORDINATES_ARR开始位|?br /> W二个|元素cd
W三个|点q接方式Q?-通过直线q接Q?-通过圆弧q接
定义?br /> CREATE TYPE sdo_elem_info_array AS VARRAY (1048576) of NUMBER;SDO_ORDINATESQ?font color="#000000">几何囑Ş所有顶点列表。定义ؓ CREATE TYPE sdo_ordinate_array AS VARRAY (1048576) of NUMBER;
FONT color=#003366>// 插入包含一个岛屿的湖泊INSERT INTO mylake VALUES(
10,
'Lake Calhoun',
MDSYS.SDO_GEOMETRY(
2003,
NULL,
NULL,
MDSYS.SDO_ELEM_INFO_ARRAY(1,1003,1, 19,2003,1),
MDSYS.SDO_ORDINATE_ARRAY(0,0, 10,0, 10,10, 0,10, 0,0, 4,4, 6,4, 6,6, 4,6, 4,4)
));
// 插入两艘船
INSERT INTO mylake VALUES(
11,
'The Windswept',
MDSYS.SDO_GEOMETRY(
2003,
NULL,
NULL,
MDSYS.SDO_ELEM_INFO_ARRAY(1,1003,1),
MDSYS.SDO_ORDINATE_ARRAY(2,2, 3,2, 3,2, 2,3, 2,2)
)
);
INSERT INTO mylake VALUES(
12,
'Blue Crest',
MDSYS.SDO_GEOMETRY(
2003,
NULL,
NULL,
MDSYS.SDO_ELEM_INFO_ARRAY(1,1003,1),
MDSYS.SDO_ORDINATE_ARRAY(7,7, 8,7, 8,7, 7,8, 7,7)
)
);
Step4. 查询
SELECT name boat_name // 选择在定义矩形内的所有小?code> // masktype可联合?br />
Oracle Spatial查询数据包括二个处理q程Q?br />1.只通过索引查询候选项。通过函数SDO_FILTER实现Q?br />
SDO_FILTER(geometry1 MDSYS.SDO_GEOMETRY, geometry2 MDSYS.SDO_GEOMETRY, params VARCHAR2)geometry1Q?/font>
必须是被索引的几何数?br />geometry2Q?/font>不一定是表中的空间字D，也不要求被烦?br />paramsQ?/font>Filtercd
querytype=WINDOWQ?/font>geometry2不要求来自表
querytype=JOINQgeometry2必须来自?/p>
FROM mylake t
WHERE feature_id = 12
AND SDO_FILTER(t.shape, mdsys.sdo_geometry(2003,NULL,NULL,
mdsys.sdo_elem_info_array(1,1003,1),
mdsys.sdo_ordinate_array(2,2, 5,2, 5,5, 2,5, 2,2)),
'querytype=WINDOW') = 'TRUE';
2.再检查每个候选项是否和条件精匹配。通过函数SDO_RELATE实现Q?br />SDO_RELATE(geometry1 MDSYS.SDO_GEOMETRY, geometry2 MDSYS.SDO_GEOMETRY, params VARCHAR2)
masktypecd
DISJOINT
?the boundaries and interiors do not intersect
TOUCH
?the boundaries intersect but the interiors do not intersect
OVERLAPBDYDISJOINT
?the interior of one object intersects the boundary and interior of the other object, but the two boundaries do not intersect. This relationship occurs, for example, when a line originates outside a polygon and ends inside that polygon.
OVERLAPBDYINTERSECT
?the boundaries and interiors of the two objects intersect
EQUAL
?the two objects have the same boundary and interior
CONTAINS
?the interior and boundary of one object is completely contained in the interior of the other object
COVERS
?the interior of one object is completely contained in the interior of the other object and their boundaries intersect
INSIDE
?the opposite of CONTAINS. A INSIDE B implies B CONTAINS A.
COVEREDBY
?the opposite of COVERS. A COVEREDBY B implies B COVERS A.
ON
?the interior and boundary of one object is on the boundary of the other object (and the second object covers the first object). This relationship occurs, for example, when a line is on the boundary of a polygon.
ANYINTERACT
?the objects are non-disjoint.
SELECT name boat_name
FROM mylake t
WHERE feature_id = 12
AND SDO_FILTER(t.shape, mdsys.sdo_geometry(2003,NULL,NULL,
mdsys.sdo_elem_info_array(1,1003,1),
mdsys.sdo_ordinate_array(2,2, 5,2, 5,5, 2,5, 2,2)),
'querytype=WINDOW') = 'TRUE'
AND SDO_RELATE(t.shape, mdsys.sdo_geometry(2003,NULL,NULL,
mdsys.sdo_elem_info_array(1,1003,1),
mdsys.sdo_ordinate_array(2,2, 5,2, 5,5, 2,5, 2,2)),
'masktype=INSIDE querytype=WINDOW') = 'TRUE'SELECT feature_id id
FROM mylake t
WHERE feature_id = 12
AND SDO_FILTER(t.shape, mdsys.sdo_geometry(2003,NULL,NULL,
mdsys.sdo_elem_info_array(1,1003,1),
mdsys.sdo_ordinate_array(2,2, 5,2, 5,5, 2,5, 2,2)),
'querytype=WINDOW') = 'TRUE'
AND SDO_RELATE(t.shape, mdsys.sdo_geometry(2003,NULL,NULL,
mdsys.sdo_elem_info_array(1,1003,1),
mdsys.sdo_ordinate_array(2,2, 5,2, 5,5, 2,5, 2,2)),
'masktype=INSIDE+TOUCH querytype=WINDOW') = 'TRUE'
Oracle Spatial 提供的其他查询函敎ͼ
Query Description SDO_NNNearest neighbor SDO_SDO_WITHIN_DISTANCEAll geometries with a certain distance Functions Description SDO_GEOM.SDO_MBRThe minimum bounding rectangle for a geometry SDO_GEOM.SDO_DISTANCEThe distance between two geometries SDO_GEOM.SDO_INTERSECTIONProvides the intersection point of two geometries
]]>
建立存储q程如下Q注意这个存储过E徏立的时候，不需要像Oracle那样建立q回的游?br />开始在Sql 2000按照Oracle那样建立了返回的游标[Sql 2000 的帮助里面也是徏立返回的游标的]Q但是调用L不成功，后来使用了没有返回游标的存储q程Qƈ且修改了调用存储q程的方式就可以了：
CREATE PROCEDURE PROC_WARE_INFO_STAT
@XX_ID bigint
AS
SELECT * FROM TableName where colname=XX_ID
GO
在调用的时候和Oracle有明昄不同Q如下：
Connection connection=xxxxxx;
CallableStatement callableStatement = connection.prepareCall("{call PROC_WARE_INFO_STAT(?) }");
callableStatement.setInt(1,100);
callableStatement.executeQuery();
ResultSet rs = callableStatement.getResultSet();
]]>
建立存储q程Q存储过EؓQ?/p>
CREATE OR REPLACE PROCEDURE TESTC(p_CURSOR out TESTPACKAGE.Test_CURSOR) IS
BEGIN
OPEN p_CURSOR FOR SELECT * FROM HYQ.TESTTB;
END TESTC;
可以看到Q它是把游标Q可以理解ؓ一个指针）Q作Z个out 参数来返回值的?/p>
在java里调用时q下面的代码：
package com.hyq.src;
import java.sql.*;
import java.io.OutputStream;
import java.io.Writer;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import oracle.jdbc.driver.*;
public class TestProcedureTHREE {
public TestProcedureTHREE() {
}
public static void main(String[] args ){
String driver = "oracle.jdbc.driver.OracleDriver";
String strUrl = "jdbc:oracle:thin:@127.0.0.1:1521:hyq";
Statement stmt = null;
ResultSet rs = null;
Connection conn = null;
try {
Class.forName(driver);
conn = DriverManager.getConnection(strUrl, "hyq", "hyq");
CallableStatement proc = null;
proc = conn.prepareCall("{ call hyq.testc(?) }");
proc.registerOutParameter(1,oracle.jdbc.OracleTypes.CURSOR);
proc.execute();
rs = (ResultSet)proc.getObject(1);
while(rs.next())
{
System.out.println("<tr><td>" + rs.getString(1) + "</td><td>"+rs.getString(2)+"</td></tr>");
}
}
catch (SQLException ex2) {
ex2.printStackTrace();
}
catch (Exception ex2) {
ex2.printStackTrace();
}
finally{
try {
if(rs != null){
rs.close();
if(stmt!=null){
stmt.close();
}
if(conn!=null){
conn.close();
}
}
}
catch (SQLException ex1) {
}
}
}
}
在这里要注意Q在执行前一定要先把oracle的驱动包攑ֈclass路径里，否则会报错的?br />
]]>
1、隐式{换导致烦引失?q一点应当引起重?也是开发中l常会犯的错?
׃表的字段tu_mdn定义为varchar2(20),但在查询时把该字D作为numbercd以where条g传给Oracle,q样会导致烦引失?
错误的例子：select * from test where tu_mdn=13333333333;
正确的例子：select * from test where tu_mdn='13333333333';
2、对索引列进行运导致烦引失?我所指的对烦引列q行q算包括(+Q?Q?Q?Q? {?
错误的例子：select * from test where id-1=9;
正确的例子：select * from test where id=10;
3、用Oracle内部函数D索引失效.对于q样情况应当创徏Z函数的烦?
错误的例子：select * from test where round(id)=10; 说明Q此时id的烦引已l不起作用了
正确的例子：首先建立函数索引Qcreate index test_id_fbi_idx on test(round(id));
然后 select * from test where round(id)=10; q时函数索引起作用了
]]>
上月末天Q?BR>SQL> select to_char(add_months(last_day(sysdate),-1),'yyyy-MM-dd') LastDay from
2 dual
3 ;
LASTDAY
----------
2004-09-30
上月今天
SQL> select to_char(add_months(sysdate,-1),'yyyy-MM-dd') PreToday from dual
2 ;
PRETODAY
----------
2004-09-29
上月首天
SQL> select to_char(add_months(last_day(sysdate)+1,-2),'yyyy-MM-dd') FirstDay
2 from dual;
FIRSTDAY
----------
2004-09-01
以下转脓Q?BR> Oracle
在日期用上允许极大的灵zL。由于可以在日期字段存储旉和日期，从而有函数可以既引用日期又引用旉?BR>Oracle 所提供的一些日期函数如下所C?BR>1. SYSDATE
q回当前的日期和旉?BR>CZ
SELECT sysdate FROM dual;
SYSDATE
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05-3?-03
2. ADD_MONTHS(d, no_of_month)
当前日期"m"后推"no_of_month" 个月。参?no_of_month"可ؓM整数?BR>CZ
SELECT add_months(sysdate,2) FROM dual;
ADD_MONTHS
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05-5?-03
SELECT add_months(sysdate,-2) FROM dual;
ADD_MONTHS
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05-1?-03
3. LAST_DAY(month_day)
q回变量"month_day"中所指定月䆾的最后一天的日期?BR>CZ
SELECT last_day(sysdate) FROM dual;
LAST_DAY(S
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31-3?-03
4. MONTHS_BETWEEN(d1, d2)
q回日期 d1 ?d2 之间的月份数。如?d1 晚于 d2Q结果ؓ正，否则q回负数?BR>CZ
SELECT months_between(sysdate,to_date('20030101','YYYYMMDD')) FROM dual;
MONTHS_BETWEEN(SYSDATE,TO_DATE('20030101','YYYYMMDD'))
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2.15773932
5. NEXT_DAY(d, day_of_week)
q回?day_of_week"命名的，在变?d"指定的日期之后的W一个工作日的日期。参?day_of_week"必须星期中的某一天?BR>CZ
-- 2003.3.2 是星期日
SELECT next_day(to_date('20030226','YYYYMMDD'),1) FROM dual;
NEXT_DAY(T
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02-3?-03
日期格式
格式元素 说明
AD ?A.D. 带有或不带有句号?AD 标记
BC ?B.C. 带有或不带有句号?BC 标记
D 一周中的天 (1-7)
DAY 天的名称 (Sunday - Saturday)
DD 一月中的天 (1 - 31)
DDD 一q中的天 (1 - 366)
DY 天的~写 (Sun - Sat)
HH 一天中的小?(1 - 12)
HH24 一天中的小?(0 - 23)
MI 分钟 (0-59)
MM ?(01-12)
MON 月名U的~写
MONTH 月的名称
SS U?(0-59)
YYYY 4 个数字表C的q?/P>