attribute_value text) AS $$BEGIN RETURN QUERY SELECT trim(both ' ' from split_part(attr, ':', 1)) AS attribute_key, trim(both ' ' from split_part(attr, ':', 2)) AS attribute_value FROM unnest(string_to_array($1, ',')) AS attr;END;$$ LANGUAGE plpgsql;SELECT * FROM split_...
The function returns a table that contains the string split in the columns with the regular expressions as separators. Below are some of the important things about the value of Regex: ● If the Regex is NULL the function will also return NULL. ● If the value of Regex is an empty string...
在PostgreSQL中,可以使用以下步骤将逗号分隔的列名转换为表: 1. 创建一个新的表,包含逗号分隔的列名。例如,假设有一个名为"table1"的表,其中有一个名为"columns"的列,包含逗...
使用split_part()，它不支持regex，因此您必须删除逗号：
13 STRING_SPLIT(str, sep) Split string to rows UNNEST(STRING_TO_ARRAY(str, sep)) 14 SUBSTRING(string, start, length) Return substring SUBSTRING(string, start, length) Datetime functions: SQL Server PostgreSQL 1 CONVERT(DATETIME, expr, style) Converts expr to datetime TO_TIMESTAMP(expr...
SELECTto_char(now(),'yyyy-MM-dd hh24:MI:ss') 3.行列转换 行转列 string_agg -- 表名为student 把学生通过年龄分组并把姓名合并起来SELECTage, string_agg(name,',')FROMstudentGROUPBYage 列转行 regexp_split_to_table SELECTregexp_split_to_table('a,b,c',',')--a--b--cSELECTregexp_spli...
columns; } for (const notice of pgresult.notices) { notice.severity; notice.message; } .stream() pgoutput messages for await (const chunk of replstream.pgoutputDecode()) { // (string) Last valid received lsn. // Use it for replstream.ack() to confirm receipt of whole chunk. chunk....
11SPLIT_PART(string, delimiter, n)Getn-th item from delimitedstringUser-defined function 12SUBSTRING(string,start,len)Get a substring ofstringSUBSTR(string,start,len) 13TIMEOFDAY()Get current date and time as stringTO_CHAR(SYSTIMESTAMP)
(4)regexp_split_to_table(string,pattern[,flags]) substring用来从一个字符串string中提取一个符合正则表达式pattern的字串,如果pattern中含有用括号括起来的子表达式,则返回符合匹配括号中的子表达式的子串。如果string中不存在匹配pattern的子串,则返回空,例如: ...
CREATE RULE statement In previous versions, it was possible to create an ON SELECT rule for a table and convert it to a view, but PostgreSQL 16 prohibits it. [b23cd18] 2.6.11. CREATE TABLE statement System columns can no longer be used as FOREIGN KEYs. This change will be backport...