MetaTable

fastdb 只有一个MetaTable，内容如下

metaTableFields[] = {
        { "name", dbField::tpString, sizeof(dbVarying),
          offsetof(dbTable, name)},
        { "fields", dbField::tpArray, sizeof(dbVarying),
          offsetof(dbTable, fields)},
        { "fields[]", dbField::tpStructure, sizeof(dbField), 0},
        { "fields[].name", dbField::tpString, sizeof(dbVarying),
          offsetof(dbField, name)},
        { "fields[].tableName",dbField::tpString,sizeof(dbVarying),
          offsetof(dbField, tableName)},
        { "fields[].inverse", dbField::tpString, sizeof(dbVarying),
          offsetof(dbField, inverse)},
//        { "fields[].type", dbField::tpInt4, 4, offsetof(dbField, type)},
        { "fields[].type", dbField::tpInt4, 4, offsetof(dbField, offset)-4},
        { "fields[].offset", dbField::tpInt4, 4, offsetof(dbField, offset)},
        { "fields[].size", dbField::tpInt4, 4, offsetof(dbField, size)},
        { "fields[].hashTable", dbField::tpReference, sizeof(oid_t),
          offsetof(dbField, hashTable)},
        { "fields[].tTree", dbField::tpReference, sizeof(oid_t),
          offsetof(dbField, tTree)},
        { "fixedSize", dbField::tpInt4, 4, offsetof(dbTable, fixedSize)},
        { "nRows", dbField::tpInt4, 4, offsetof(dbTable, nRows)},
        { "nColumns", dbField::tpInt4, 4, offsetof(dbTable, nColumns)},
        { "firstRow", dbField::tpReference, sizeof(oid_t), offsetof(dbTable, firstRow)},
        { "lastRow", dbField::tpReference, sizeof(oid_t), offsetof(dbTable, lastRow)}
#ifdef AUTOINCREMENT_SUPPORT
       ,{ "count", dbField::tpInt4, 4, offsetof(dbTable, count)}
#endif
    };

 

MetaTable，其实里面什么也没有存，只起一个标记作用，它有一个next指针，指向第一个创建的表，当查找表时，就从MetaTable表的next指针依次向后找，所有的表构成一个双向链表。

这主要是因为MetaTable的oid是固定的，为1