你需要明白的索引和约束的前缀（AK,PK,IX,CK,FK,DF,UQ）

PK - Primary Key

IX - Non-Unique Index

AK - Unique Index (AX should have been AK (Alternate Key))

CK - Check Constraint

DF - Default Constraint

FK - Foreign Key

UQ - Unique Constraint

转载于:https://www.cnblogs.com/flysun0311/archive/2013/02/28/2936588.html