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[Source] Mysql NN means

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Posted on 8/8/2017 3:25:38 PM | | | |


- PK: primary key (column is part of a pk)
- NN: not null (column is nullable) is empty
- UQ: unique (column is part of a unique key)
- AI: auto increment (the column is auto incremented when rows are inserted) is automatically incremented
- BIN: binary (if dt is a blob or similar, this indicates that is binary data, rather than text)
- UN: unsigned (for integer types, see docs: “10.2. Numeric Types”)
- ZF: zero fill (rather a display related flag, see docs: “10.2. Numeric Types”)



NN ticks the representative: can't be empty!
NN unchecked: Yes is empty!




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