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MySQL Workbench建表時(shí)PK, NN, UQ, BIN, UN...的意思

2015.09.10 | 488閱讀 | 0條評(píng)論 | 數(shù)據(jù)庫(kù)

  1. - PK: primary key (column is part of a pk) ?主關(guān)鍵字
  2. - NN: not null (column is nullable) ? 不能為空
  3. - UQ: unique (column is part of a unique key) ? ??唯一的
  4. - AI: auto increment (the column is auto incremented when rows are inserted) ??自動(dòng)加數(shù)
  5. [additional data type flags, depend on used data type]
  6. - BIN: binary (if dt is a blob or similar, this indicates that is binary data, rather than text) ? 二進(jìn)制
  7. - UN: unsigned (for integer types, see docs: “10.2. Numeric Types”)
  8. - ZF: zero fill (rather a display related flag, see docs: “10.2. Numeric Types”)
 

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