oracle sql日期比較:
在今天之前:select?*?from?up_date?where?update?<?to_date('2007-09-07?00:00:00','yyyy-mm-dd?hh24:mi:ss')
select?*?from?up_date?where?update?<=?to_date('2007-09-07?00:00:00','yyyy-mm-dd?hh24:mi:ss')
在今天只后:select?*?from?up_date?where?update?>?to_date('2007-09-07?00:00:00','yyyy-mm-dd?hh24:mi:ss')
select?*?from?up_date?where?update?>=?to_date('2007-09-07?00:00:00','yyyy-mm-dd?hh24:mi:ss')
精確時間:select?*?from?up_date?where?update?=?to_date('2007-09-07?00:00:00','yyyy-mm-dd?hh24:mi:ss')
在某段時間內:select?*?from?up_date?where?update?between?to_date('2007-07-07?00:00:00','yyyy-mm-dd?hh24:mi:ss')?and?to_date('2007-09-07?00:00:00','yyyy-mm-dd?hh24:mi:ss')
select?*?from?up_date?where?update?<?to_date('2007-09-07?00:00:00','yyyy-mm-dd?hh24:mi:ss')?and?update?>?to_date('2007-07-07?00:00:00','yyyy-mm-dd?hh24:mi:ss')
select?*?from?up_date?where?update?<=?to_date('2007-09-07?00:00:00','yyyy-mm-dd?hh24:mi:ss')?and?update?>=?to_date('2007-07-07?00:00:00','yyyy-mm-dd?hh24:mi:ss')
posted @
2007-09-07 16:29 forker 閱讀(88483) |
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?? MySql的備份可用命令mysqldump ,使用方法很簡單,mysqldump -u?用戶名 -p (密碼)?-h 主機名 數據庫名
>路徑/備份名.bak;同時也可以是用mysqldump到處數據結構(tablename.sql)和數據(tablename.txt)
mysqldump -u?用戶名??-p (密碼)? -h 主機名 數據庫名 tablename1 tablename2 >
back.sql或mysqldump -u?用戶名?-p (密碼) -h 主機名 數據庫名 --tab 路徑 --opt 數據庫名.
???那么還原可以mysql命令,mysql -u?用戶名?-p (密碼) -h 主機名 --one-database 還原數據庫名 < 路徑/備份名.bak,--one-database是指定要恢復的數據庫.
? (括號表示密碼不先輸入,在連接時在Enter password;若密碼為空可缺省-p參數)
posted @
2007-09-06 17:08 forker 閱讀(1300) |
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???? 安裝有oracle數據庫,創建數據庫,總是要創建一個主鍵ID,唯一標示各條記錄,但oracle不支持自動編號,所以還得創建一個SEQUENCE(序列)語句如
????
create?sequence?bign?nocycle?maxvalue?9999999999?start?with?1;//增加數據
insert?into?table?(ID,..)?values(bign.nextval,..)
???? 在hibernate中的映射文件可這么寫
?? <id?name="id"?type="java.lang.Long"?column="ID">
????????????<generator?class="sequence"?>
?????????????????<param?name="sequence">bign</param>
????????????</generator>
???</id>
或
? <id?name="id"?type="java.lang.Long"?column="ID">
????????????<generator?class="increment"?>
??</id>
(increment 用與為long,short或者int類型生成唯一標示。只有在沒有其他進程忘同一張表中插入數據時才能使用。在集群下不要使用)
posted @
2007-08-28 15:12 forker 閱讀(4071) |
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Hibernate加載其配置文件hibernate.properties和hibernate.cfg.xml,常用xml文件比較直觀,方便管理,
Hibernate
是一個流行的開源對象關系映射工具,方便連接不同數據庫,更換數據庫,只要修改Hibernate配置文件,大度減少項目的維護。
完整的配置如下:
<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<!-- Database connection settings -->
<property name="connection.driver_class">org.hsqldb.jdbcDriver</property>
<property name="connection.url">jdbc:hsqldb:hsql://localhost/test</property>
<property name="connection.username">sa</property>
<property name="connection.password"></property>
<!-- JDBC connection pool (use the built-in) -->
<property name="connection.pool_size">1</property>
<!-- SQL dialect -->
<property name="dialect">org.hibernate.dialect.HSQLDialect</property>
<!-- Enable Hibernate's automatic session context management -->
<property name="current_session_context_class">thread</property>
<!-- Disable the second-level cache -->
<property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property>
<!-- Echo all executed SQL to stdout -->
<property name="show_sql">true</property>
<!-- Drop and re-create the database schema on startup -->
<property name="hbm2ddl.auto">create</property>
<mapping resource="../*.hbm.xml"/>
</session-factory>
</hibernate-configuration>
常用數據庫連接
MySql 3/4/5:
<property name="dialect">org.hibernate.dialect.MySQLDialect</property>
<property name="connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="connection.url">jdbc:mysql://localhost:3306/test</property>
<property name="connection.username">root</property>
<property name="connection.password"></property>
Microsoft SQLServer (via jTDS):
<property name="dialect">org.hibernate.dialect.SQLServerDialect</property>
<property name="connection.driver_class">net.sourceforge.jtds.jdbc.Driver</property>
<property name="connection.url">jdbc:jtds:sqlserver://localhost:1433/test;useCursors=true</property>
<property name="connection.username">sa</property>
<property name="connection.password"></property>
IBM DB2:
<property name="dialect">org.hibernate.dialect.DB2Dialect</property>
<property name="connection.driver_class">com.ibm.db2.jcc.DB2Driver</property>
<property name="connection.url">jdbc:db2://localhost:50000/test</property>
<property name="connection.username">db2inst1</property>
<property name="connection.password"></property>
Oracle:
<property name="dialect">org.hibernate.dialect.OracleDialect</property>
<property name="connection.driver_class">oracle.jdbc.driver.OracleDriver</property>
<property name="connection.url">jdbc:oracle:thin:@localhost:1521:test</property>
<property name="connection.username">ora</property>
<property name="connection.password"></property>
Informix:
<property name="dialect">org.hibernate.dialect.InformixDialect</property>
<property name="connection.driver_class">com.informix.jdbc.IfxDriver</property>
<property name="connection.url">jdbc:informix-sqli://localhost:1526/test:informixserver=server1</property>
<property name="connection.username">root</property>
<property name="connection.password"></property>
<property name="connection.encoding">true</property>
Sybase (via jTDS):
<property name="dialect">org.hibernate.dialect.SybaseDialect</property>
<property name="connection.driver_class">net.sourceforge.jtds.jdbc.Driver</property>
<property name="connection.url">jdbc:jtds:sybase://localhost:7100/test;useCursors=true</property>
<property name="connection.username">root</property>
<property name="connection.password"></property>
PostgreSQL:
<property name="dialect">org.hibernate.dialect.PostgreSQLDialect</property>
<property name="connection.driver_class">org.postgresql.Driver</property>
<property name="connection.url">jdbc:postgresql://localhost:5432/test</property>
<property name="connection.username">root</property>
<property name="connection.password"></property>
MaxDB(SAPDB):
<property name="dialect">org.hibernate.dialect.SAPDBDialect</property>
<property name="connection.driver_class">com.sap.dbtech.jdbc.DriverSapDB</property>
<property name="connection.url">jdbc:sapdb://localhost/test</property>
<property name="connection.username">root</property>
<property name="connection.password"></property>
posted @
2007-08-21 10:01 forker 閱讀(4124) |
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最近在想能做點什么,該做點什么。
posted @
2007-08-15 16:54 forker 閱讀(729) |
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