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1.pgsql 分頁查詢
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select * from table_name limit A offset B
注：A為所需展示的行數
B為查詢的起始位置
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select * from table_name where id >B limit A
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2.pgsql 擷取字串函式
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給定子字串在字串中的位置 position ('源字串','子字串')
擷取字串 substring('源字串' from 起始位置 for 擷取字串長度);
substring('源字串',A,B);
注：A:起始位置 B.擷取長度
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3.pgsql 遞迴查詢
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從根節點往子節點查詢：
with recurse result as(
select id,pid,name from js_city where id=1
union all
select a.id,a.pid,a.name from js_city a join result b on b.id= a.pid)
select id,pid,name from result;