mco_uda_pattern_search

原型

    MCO_RET mco_uda_pattern_search(	/*IN*/ mco_trans_h t, 
                      /*IN*/ unsigned short struct_no, 
                      /*IN*/ unsigned short index_no,
                       /*IN*/ const mco_uda_value_t * keys, 
                      /*IN*/ unsigned short keys_count, 
                      /*INOUT*/ mco_cursor_t * cursor, 
                      /*INOUT*/ void * allocated_pattern );

参数

t	事务处理
struct_no	结构/类编号（必须介于 0 和 - 1 之间）mco_dict_struct_count()
index_no	索引号（必须介于 0 和 - 1 之间）struct_info.index_count
keys	搜索键数组
keys_count	搜索键数组的长度请注意，键的数量、它们的顺序和类型必须与索引的 DDL 描述相对应
keys	光标手柄
allocated_pattern	搜索模式

描述

执行数据库模式搜索。

返回

MCO_E_UDA_STRUCT_NOTFOUND	无效struct_no
MCO_E_UDA_STRUCT_NOT_CLASS	无效 （不是类）struct_no
MCO_E_UDA_INDEX_NOTFOUND	无效index_no
MCO_E_UDA_WRONG_KEY_NUM	值无效 - 与索引定义不匹配keys_count
MCO_E_UDA_WRONG_KEY_TYPE	密钥类型不匹配

示例

    Sample schema :
     
    class TestClass
    {
        string 		key;
        char<20> 	k2;
        int4 		k3;
        int4 		v1;
         
        tree <key,k2,k3> i1;
    };
     
    /*  应用程序代码片段 */
     
    MCO_RET psearch(mco_db_h db, char* pattern1, char* pattern2, int p3, mco_bool ignore_other_fields)
    {
        MCO_RET rc = MCO_S_OK;
        mco_trans_h trn;
        mco_cursor_t csr;
        mco_uda_object_handle_t obj;
        uint2 size1;
        uint4 bsize;
        char key[64], k2[64];
        int4 k3, v1;
        void * buf;
        mco_pattern_policy_t p;
        unsigned short s_no = get_struct_no("TestClass");
        unsigned short i_no = get_index_no(s_no, "i1");
        unsigned short f_no;
        mco_uda_value_t keys[3], value;
         
        /* Get memory for set of patterns */
        keys[0].type = MCO_DD_STRING;
        keys[0].v.p.p.c = pattern1;
        keys[0].v.p.len = (uint2)strlen(pattern1);
        keys[1].type = MCO_DD_CHAR;
        keys[1].v.p.p.c = pattern2;
        keys[1].v.p.len = (uint2)strlen(pattern2);
         
        keys[2].type = MCO_DD_INT4;
        keys[2].v.i4   = p3;
        mco_uda_pattern_size(metadict, 0, s_no, i_no, keys, 3, &bsize);
        buf = malloc(bsize);
         
        /* start read-write transaction to change pattern policy */
        rc = mco_trans_start(db, MCO_READ_WRITE, MCO_TRANS_FOREGROUND, &trn);
        if ( MCO_S_OK == rc ) 
        {
            mco_get_pattern_policy(trn, &p);
            p.ignore_other_fields = ignore_other_fields; /* ignore fields other than char<n> or string */
            mco_set_pattern_policy(trn, &p);
            rc = mco_uda_cursor(trn, s_no, i_no, &csr);
            for (rc = mco_uda_pattern_search(trn, s_no, i_no, keys, 3, &csr, buf);
                rc == MCO_S_OK; rc = mco_uda_pattern_next(trn, &csr, buf))
            {
                mco_uda_from_cursor(trn, &csr, &test);
                /* Do something with the current UDA object */
                ...
            }
        }
    }
         
         
    int main(int argc, char** argv)
    {
        MCO_RET rc;
        ...
        char * pattern1 = "abc_1*";
        char * pattern2 = "??c_?2?";
        int    pattern3 = 1;
        ...
        rc = psearch(db, pattern1, pattern2, pattern3, MCO_NO);
        if (MCO_S_OK == rc) 
        {
            printf("\n\tStart search using all patterns and ignore other index components\n");
            psearch(db, pattern1, pattern2, pattern3, MCO_YES);
        }
        ...
    }