spool 导出路径 --该语句可理解为获取emp表的ddl语句然后显示到dual(注意:get_ddl()内均需大写——建表 select dbms_metadata.get_ddl('TABLE','表名') from dual; --数据插入(若列数据类型为number则书写格式为'||列名||') select'insert into 表名 values('''||列名1||''','''||列名2||''',...
1.虚拟表dual 存在虚拟表dual查询 例:select 2 num from dual直接去掉dual表(oracle示例) 例:select 2 num(pg库示例) 2.使用rownum 分页查询 例: AI检测代码解析 (select * from ( select *,rownum rownum from (A) row_ where rownum <= endIndex) where rownum_ > startIndex 1. 2. AI检测代码解析...
Postgresql, 求一条sql. 产生n行结果: result === 1 2 3 ... n oracle的类似语法: select level from dual connect by level<= 10;postgresql 有用关注2收藏 回复 阅读5.9k 2 个回答 得票最新 brayden 4.6k32028 发布于 2016-08-04 更新于 2016-08-17 ✓ 已...
复制表结构及数据到新表 CREATE TABLE 新表 SELECT * FROM 旧表 只复制表结构到新表 CREATE TABLE 新表 SELECT * FROM 旧表 WHERE 1=2 即:让...方法二:(由tianshibao提供) CREATE TABLE 新表 LIKE 旧表 复制旧表的数据到新表(假设两个表结构一样) INSERT INTO 新表 SELECT * FROM 旧表 复制旧表的...
In Oracle the statement SELECT SUBSTR(‘ABC’,-1) FROM DUAL; returns ‘C’, while the equivalent SELECT SUBSTR('ABC',-1); in Postgres would return ABC. The Orafce migration tool includes a SUBSTR function that returns the same result in both databases. 16. SynonymsPostg...
在数据库权限新建的test库,可以看到dual表的grantee为PUBLIC test=>\c test sa Youarenow connectedtodatabase "test"asuser"sa". test=#select*fromINFORMATION_SCHEMA.role_table_grantswheretable_catalog='test'andtable_name='dual'andgrantee='PUBLIC'; ...
...=# DELETE FROM my_tab where i=1; DELETE 1 以与start_lsn相同的方式获取end_lsn: postgres=# SELECT pg_current_wal_lsn...第一印象是 wal 记录的数量很多:仅针对几个 SQL 操作就生成了 100 条记录。如果wal_level设置为logical,记录数会增加(如果设置为minimal则记录数当然会减少)。......
select*fromdual;orselectsysdate; Recent Comments Add New Comment PleaseLog Into comment on this post. Migrate Now from Oracle to Postgres Transform your data management with a robust open source platform Contact Us More Blogs Comprehensive Guide on How to Tune Database Parameters and Configuration ...
SELECT '01.00^01.13' AS "COLUMN_VALUE" FROM DUAL UNION ALL SELECT '01.00 01.15' AS "COLUMN_VALUE" FROM DUAL) ORDER BY 1; COLUMN_VALUE 01.00 01.12 01.00 01.15 01.00^01.13 但是,当我在Postgres中执行排序时,它排序为: SELECT * FROM ( ...
SELECT TO_CHAR(SYSTIMESTAMP, 'SSSSS.FF') FROM DUAL; SeeSection 9.9.4for more details. If you have setlightdb_syntax_compatible_typeto oracle, then the result of expression "value || NULL" will be the value, otherwise the result will be NULL. ...