to_char 函数 to_char(expre, format) 函数用于将 timestamp、interval、integer、double precision 或者 numeric 类型的值转换为指定格式的字符串。 SELECT to_char(current_timestamp, 'HH24:MI:SS'), to_char(interval '5h 12m 30s', 'HH12:MI:SS'), to_char(-125.8, '999D99'); to_char |to_...
to_char(numeric, text) text 数字转换为字符串 to_char(-125.8, '999D99S') to_date(text, text) date 字符串转换为日期 to_date('05 Dec 2000', 'DD Mon YYYY') to_number(text, text) numeric 转换字符串为数字 to_number('12,454.8-', '99G999D9S') to_timestamp(text, text) timestamp...
New to PostgreSQL? PostgreSQL is a powerful, open source object-relational database system with over 35 years of active development that has earned it a strong reputation for reliability, feature robustness, and performance. There is a wealth of information to be found describing how toinstalland...
详情见官网:http://www.postgres.cn/docs/10/functions-formatting.html PostgreSQL中有以下格式化函数: 1.将数值转成字符串类型to_char(int,text):参数1为要转换值,参数2为数值格式化模式,其中用于数字格式化的模板模式为: 1.1当模式串大于等于于数字个数时,字符串正常显示: 1.2当模式串小于数字个数时,字符串会...
PostgreSQL中提供了三种实现模式匹配的方法:SQL LIKE操作符,更近一些的SIMILAR TO操作符,和POSIX-风格正则表达式。 1. LIKE: string LIKE pattern [ ESCAPE escape-character ] string NOT LIKE pattern [ ESCAPE escape-character ] 每个pattern定义一个字串的集合。如果该string包含在pattern代表的字串集合里,那么LI...
In the above example, we first establish a connection to the PostgreSQL database using the JDBC API. We then insert anumericvalue into a table using a prepared statement. Finally, we retrieve the value from the table and print it to the console. ...
--用substring截取字符串,从第8个字符开始截取2个字符:结果是12 selectcast(substring('1234abc12',8,2)asinteger) ---使用to_number函数来转换成整数 ---to_number(text, text) 返回的类型 numeric 把字串转换成numeric to_number('12,454.8-', '99G999D9S') ...
Each argument to this function represents a bit in the bit vector. This function takes as arguments any numeric datatype, or any nonnumeric datatype that can be implicitly converted to NUMBER. Each expr must evaluate to 0 or 1. This function returns Oracle NUMBER. 例子 SELECT BIN_TO_NUM(...
select cast('1234'as integer) ;--⽤substring截取字符串，从第8个字符开始截取2个字符：结果是12 select cast(substring('1234abc12',8,2) as integer)---使⽤to_number函数来转换成整数 ---to_number(text, text) 返回的类型 numeric 把字串转换成numeric to_number('12,454.8-', '99G...
问PostgreSQL : to_number()函数EN1、我们都知道在SQL中有一类函数叫做聚合函数,例如sum()、avg()、...