RELATION主题的文章列表，还有RELATION的技术要点_第3页

ORA-19000: missing RELATIONAL keyword

文档解释ORA-19000:missingRELATIONALkeywordCause:ThekeywordRELATIONALintheworkOBJECTRELATIONALismissingintheXMLTYPEstorageclausespecification.Action:SupplytheRELATIO...

IT技术学习 ·2023-07-10

ORA-31165: cannot load object-relational XML attribute using direct path

文档解释ORA-31165:cannotloadobject-relationalXMLattributeusingdirectpathCause:Thetablebeingloadedcontainsaxmlcolumnwithobject-relationalstorage.Thexmltypecolumneith...

IT技术学习 ·2023-07-10

ORA-48318: ADR Relation [string] of version=string cannot be supported

文档解释ORA-48318:ADRRelation[string]ofversion=stringcannotbesupportedCause:theversionofADRrelationistoonewandcannotbesupportedAction:needtouseanewerreleasetoaccess...

IT技术学习 ·2023-07-10

ORA-30368: ATTRIBUTE cannot determine column in a different relation

文档解释ORA-30368:ATTRIBUTEcannotdeterminecolumninadifferentrelationCause:AnATTRIBUTEclauseinadimensionstatementspecifiedadeterminedcolumnontherightthatisinadiffere...

IT技术学习 ·2023-07-08

ORA-30365: left relation in the JOIN KEY clause cannot be same as right

文档解释ORA-30365:leftrelationintheJOINKEYclausecannotbesameasrightCause:TherelationofthechildcolumnsontheleftsideoftheJOINKEYclausewasthesameasthatoftheparentlevel...

IT技术学习 ·2023-07-08

ORA-48506: Existing Relation at different version than export [string] [string]

文档解释ORA-48506:ExistingRelationatdifferentversionthanexport[string][string]Cause:Attemptingtoimportintoanexistingrelationandtheschemaversionofthatrelationdiffers...

IT技术学习 ·2023-07-08

ORA-48322: Relation [string] of ADR V[string] incompatible with V[string] tool

文档解释ORA-48322:Relation[string]ofADRV[string]incompatiblewithV[string]toolCause:thetoolversionisincompatiblewiththeADRversionAction:useanotherversionoftoolandret...

IT技术学习 ·2023-07-06

PostgreSQL ----- No relations found.

本篇文章可能有错，尚未细细研究运行d出错：Norelationsfound.d只显示可见的表，也就是该数据库的schema在search_path中。SHOWsearch_path;如果没有，设置一下：SETsearch_path=tran;其中tran是要查询的schema。如果d仍然出错，查看一下访问权...

代码星球 ·2021-02-21

Congruence relation 同余关系

https://en.wikipedia.org/wiki/Congruence_relation https://zh.wikipedia.org/wiki/%E5%90%8C%E9%A4%98%E9%97%9C%E4%BF%82 在数学特别是抽象代数中，同余关系或简称同余是相容于某个...

代码星球 ·2020-11-25

bug之needs to have a value for field "id" before this many-to-many relationship can be used.

一、环境配置　　操作系统：WIndows64　　django版本：3.0.3　　数据库：mysql二、报错代码c=Category()c.name=cleaned_data.get("name")c.brief=cleaned_data.get("brief")c.author.add(User.objects.get...

代码星球 ·2020-06-14

django 操作数据库--orm(object relation mapping)---models

思想django为使用一种新的方式，即：关系对象映射（ObjectRelationalMapping，简称ORM）。　　PHP：activerecord　　Java：Hibernate 　C#：Entity Frameworkdjango中遵循CodeFrist的原则，即：根...

代码星球 ·2020-06-13

pgsql 执行建库脚本时候出现ERROR: relation "xxx_id_seq" does not exist

1.问题：ERROR:relation"xxx_id_seq"doesnotexist 2.出现原因：由于表中建立了自增字段，id定义为Serial类型，当执行完成建表语句后，其字段便成int4NOTNULLDEFAULTnextval('"xxx".xxx_id_seq'::regclass)　　由于xxx...

代码星球 ·2020-05-23

皮尔逊相关系数（Pearson Correlation Coefficient，Pearson's r）

Pearson'sr，称为皮尔逊相关系数（Pearsoncorrelationcoefficient），用来反映两个随机变量之间的线性相关程度。用于总体（population）时记作ρ (rho)（populationcorrelationcoefficient）：给定两个随机变量X,Y，...

代码星球 ·2020-04-12