select initcap(concat(last_name,first_name)) "姓名" from employees where initcap(concat(last_name,first_name)) like '%a%' and initcap(concat(last_name,first_name)) like '%e%'; 11.显示系统时间 写法一: Select sysdate from dual; 写法二: Select current_timestamp from dual; 12.查询员工号...
select current_timestamp; 获取时间戳 就是日期时间 ===在SqlServer数据库 中用如下语句: select getdate() ===在Oracle数据库 中用如下语句: Oracle自带的获取当前机器的系统时间的函数: Select To_Char (SYSDATE,'MM-DD-YYYY HH24:MI:SS') "now" from dual; 将系统时间赋给now参数....
view, or materialized view. Oracle Database returns a set of column in the order in which the columns were specified when the object was created. A query that selects rows from two or more tables, views, or materialized views is a join. ...
Use a SELECT statement or subquery to retrieve data from one or more tables, object tables, views, object views, or materialized views. If part or all of the result of a SELECT statement is equivalent to an existing materialized view, then Oracle Database may use the materialized view in...
import java.sql.*; import java.text.SimpleDateFormat; public class TestOBOraclePSInsertAppend { public static void main(String[] args) { try { String timeStr = null; SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); timeStr = formatter.format(new Date(System.cu...
SelectDB 2.X版本仅对Oracle数据库有效。在查询时,会将所有的库名和表名转换为大写,再查询 Oracle。例如 Oracle在TEST空间下有TEST表,SelectDB在创建Catalog时设置lower_case_table_names=true,则SelectDB可以通过SELECT * FROM oracle_catalog.test.test查询到TEST表,SelectDB会自动将test.test格式化成TEST.TEST下...
云数据库 SelectDB 版完全兼容Apache Doris,支持通过Flink Doris Connector将MySQL、Oracle、PostgreSQL、SQL Server、Kafka等数据源中的历史数据导入至SelectDB。同时,在Flink开启CDC任务后,数据源的增量数据也会同步至SelectDB。 功能简介 说明 Flink Doris Connector目前仅支持向SelectDB写数据,如果您有读取SelectDB数据...
Oracle|to_date()格式化日期【坑】 SQL1:结果159条 select count(1) from daily_file_information where 1=1 and to_char(dfi_create_time,'yyyy-mm...') between '2020-03' and '2020-05' ; SQL2:结果155条 select count(1) from daily_file_information where...1=1 and dfi_create_time between...
MASTER_POS_WAIT(log_name, log_pos[,timeout]) N NAME_CONST(name,value) N RELEASE_LOCK(str) N SLEEP(duration) N UUID() N UUID_SHORT() N VALUES(col_name) N SELECT语句支持的Oracle函数 HybridDB for MySQL目前支持在SELECT查询语句中使用如下的Oracle函数: 表15. 操作符 函数名说明别名是否支持...
month(date):获取指定时间的月份 year(date):获取指定时间的年份 select CONVERT(varchar(12) , getdate(), 101 ) Oracle查询系统时间 法一:select sysdate from dual; 法二:select Current_date from dual; 法三:select SYSTIMESTAMP from dual;