php - MYSQL like a join but only need the newest row? -


मैं निम्नलिखित करना चाहता हूं लेकिन एक प्रश्न में: 

  $ query = mysql_query ( "चयन नाम से tbl_users WHERE श्रेणी = '1'"); जबकि ($ पंक्ति = mysql_fetch_assoc ($ query)) {$ query2 = mysql_query ("तिथि से निर्धारित तिथि से दिनांकित तिथि से दिनांकित DESC LIMIT 1"); $ Row2 = mysql_fetch_assoc ($ query2); प्रति पंक्ति गूंज ['नाम'] "& Gt;" $ पंक्ति 2 ['तिथिबद्ध']। "& Lt; br / & gt;"; }

एक उपयोगकर्ता तालिका और एक टिप्पणी तालिका है, मैं उपयोगकर्ताओं की सूची और उनके पास अंतिम टिप्पणी की तारीख प्रदर्शित करना चाहते हैं?

क्या यह संभव है कि एक एकल प्रश्न में?

आप निम्न SQL का उपयोग करके ऐसा कर सकते हैं: 

  SELECT name, (SELECT datecreated FROM tbl_comments WHERE tbl_users.user_id = tbl_comments.user_id ORDER तिथि के अनुसार LIMIT 1) Tbl_users से WHERE श्रेणी = '1';

या का उपयोग कर: 

  SELECT tbl_users.name, MAX (datecreated) के रूप में ताज़ा टिप्पणी से tbl_users LEFT JOIN tbl_comments ON (tbl_users.user_id = tbl_comments.user_id) समूह द्वारा tbl_users.name;

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