Interbase/Firebird的SQL语法

二、显示表名和表结构
　　SHOW TABLES;
     SHOW TABLE tablename;

三、使用ISQL连接数据库
  firebird%92bin>isql -u sysdba -p masterkey
  SQL>CONNECT 'E:companyxmwsoftnewxmwsoftc2dbcts2.fdb';
  或
  SQL>CONNECT 'E:%92'
  CON>USER 'sysdba'
  CONT>PASSWORD 'masterkey';

四、更新字段注释
  UPDATE RDB$RELATION_FIELDS
  SET RDB$DESCRIPTION = '描述信息'
  WHERE (RDB$RELATION_NAME = 'SHOP')
    AND (RDB$FIELD_NAME = 'CREDIT_BUY')

五、显示字段注释
  SELECT RDB$FIELD_NAME,RDB$DESCRIPTION
  FROM RDB$RELATION_FIELDS
  WHERE (RDB$RELATION_NAME = 'SHOP')
    AND (DB$FIELD_NAME = 'CREDIT_BUY')

六、更新表注释
  UPDATE RDB$RELATIONS
  SET RDB$DESCRIPTION = '描述信息'
  WHERE RDB$RELATION_NAME = 'TABLE_NAME';

七、查询所有的表和视图（包括系统表和系统视图）
  SELECT RDB$RELATION_NAME
  FROM RDB$RELATIONS;

八、查询所有的用户表和用户视图
  SELECT RDB$RELATION_NAME
  FROM RDB$RELATIONS
  WHERE RDB$SYSTEM_FLAG = 0;

九、查询所有的用户表
  SELECT RDB$RELATION_NAME
  FROM RDB$RELATIONS
  WHERE RDB$SYSTEM_FLAG = 0
    AND RDB$VIEW_BLR IS NULL;

十、查所有用户表、用户视图所有字段及相关定义
  SELECT
    a.RDB$RELATION_NAME,
    b.RDB$FIELD_NAME,
    b.RDB$FIELD_ID,
    d.RDB$TYPE_NAME,
    c.RDB$FIELD_LENGTH,
    c.RDB$FIELD_SCALE
  FROM RDB$RELATIONS a
    INNER JOIN RDB$RELATION_FIELDS b
      ON a.RDB$RELATION_NAME = b.RDB$RELATION_NAME
    INNER JOIN RDB$FIELDS c
      ON b.RDB$FIELD_SOURCE = c.RDB$FIELD_NAME
    INNER JOIN RDB$TYPES d
      ON c.RDB$FIELD_TYPE = d.RDB$TYPE
  WHERE a.RDB$SYSTEM_FLAG = 0
    AND d.RDB$FIELD_NAME = 'RDB$FIELD_TYPE'
  ORDER BY a.RDB$RELATION_NAME, b.RDB$FIELD_ID;

十一、查找某表的所有字段及相关定义
  SELECT
    A.RDB$FIELD_NAME,
    B.RDB$FIELD_TYPE,
    B.RDB$FIELD_LENGTH,
    B.RDB$FIELD_PRECISION,
    B.RDB$FIELD_SCALE
  FROM RDB$RELATION_FIELDS A, RDB$FIELDS B
  WHERE A.RDB$RELATION_NAME = 'tablename'
    AND A.RDB$FIELD_SOURCE = B.RDB$FIELD_NAME
  ORDER BY A.RDB$FIELD_POSITION;

十二、查找某表的主键定义字段
  SELECT A.RDB$FIELD_NAME
  FROM RDB$INDEX_SEGMENTS A, RDB$RELATION_CONSTRAINTS B
  WHERE B.RDB$CONSTRAINT_TYPE = 'PRIMARY KEY'
    AND B.RDB$RELATION_NAME = 'tablename'
    AND A.RDB$INDEX_NAME = B.RDB$INDEX_NAME
  ORDER BY A.RDB$FIELD_POSITION;

十三、查找某表的外键定义 
  SELECT
    r1.RDB$CONSTRAINT_NAME,
    rind.RDB$FIELD_NAME,
    r2.RDB$RELATION_NAME
  FROM
    RDB$RELATION_CONSTRAINTS r1,
    RDB$RELATION_CONSTRAINTS r2,
    RDB$REF_CONSTRAINTS ref,
    RDB$INDEX_SEGMENTS rind
  WHERE r1.RDB$RELATION_NAME = 'tablename'
    AND r1.RDB$CONSTRAINT_TYPE = 'FOREIGN KEY'
    AND r1.RDB$CONSTRAINT_NAME = ref.RDB$CONSTRAINT_NAME
    AND ref.RDB$CONST_NAME_UQ = r2.RDB$CONSTRAINT_NAME
    AND r1.RDB$INDEX_NAME = rind.RDB$INDEX_NAME;