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CS186 杂记

CS186 数据库课程学习杂记

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作者 Shane Anderson
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SQL2

  1. SQL Language

    Two sublanguages:

    • DDL: Definition
    • DML: Manipulation

  2. DDL

    Primary Key column(s):

    • Unique.
    • Can be made up of > 1 column. E.g. (firstname, lastname)

  3. DML

    • SELECT
    • SELECT DISTINCT
    • LIMIT: Typically used with ORDER BY
    • Aggregates;;
SQL
CS186 SQL
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