09 2004 档案
摘要:oracle: OracleConnectionOcon=newOracleConnection("userid=cmes;datasource=mes;password=cmes"); OracleCommandOcom=newOr...
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摘要:Understanding Relationship Existence Existence describes the relationship between a pair of entities from the perspective of the child entity. Fundamentally, it asks the question, "Is a foreign key...
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摘要:Understanding Relationship Cardinality Cardinality describes the quantitative dimension in the relationship between a pair of entities as viewed from the perspective of the parent entity. Fundament...
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摘要:Understanding Relationship Types DEF1X supports three relationship types: Identifying Non-Identifying Non-Specific The selection of relationship types is fundamental to the referential integri...
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