text: #ifndef DATATAB_H_
  #define DATATAB_H_
  
  enum Type{
  	INPUT_INTEGER, INPUT_STRING
  };
  
  typedef struct _Value{
  	char* value;
  	struct _Value *next;
  }Value;
  
  typedef struct _field{
  
  	char* col_name;
  	char* alias;
  	enum Type type;
  	Value *R;//数据的跟跑指针
  	Value *data;
  }*Field;
  
  typedef struct _table{
  	char* table_name;
  	char* alias;
  	int col_num;//列的数目
  	int row_num;//行的数目
  	Field fields[100];//列首指针
  }Table;
  
  void create_table();
  int isExistsTable(char* table_name);
  int isExistsCol(char* table_name,char* col_name);
  Table* new_table();
  Table* getTable(char* tab_name);
  Field getField(Table* table, char* col_name);
  void update_field_by_row(int row, Field field,char* val);
  void insert_value_in_field(Field field,char* col_value);
  int getIndexByTabName(char* tab_name);
  void write_cols(char* tab_name);
  void outputResultset(char* msg);
  void newLine();
  void close_file();
  
  #endif
  