[JesterlJoker]

Ahh I see the problem

PHP код:

    for(new i = 0; i < MAX_ENTRANCES; i ++) 
    { 
        if(!EntranceInfo[i][eExists]) 
        { 
            mysql_format(connectionID, queryBuffer, sizeof(queryBuffer), "INSERT INTO entrances (name, pos_x, pos_y, pos_z, pos_a, outsideint, outsidevw) VALUES('%e', '%f', '%f', '%f', '%f', %i, %i)", name, x, y, z, a - 180.0, GetPlayerInterior(playerid), GetPlayerVirtualWorld(playerid)); 
            mysql_tquery(connectionID, queryBuffer, "OnAdminCreateEntrance", "iisffff", playerid, i, name, x, y, z, a); 
            break; // Use break instead of return 1; It'll stop the loop.
        } 
    } 


Check this out link!

As I've seen the loop continues up to the MAX_ENTRANCES you have made for your server, it does not get stopped because you were using return and not break.