第四章 查询语句：MongoDb VS MySql 4.2
? Conditional Operators
, >=,$ne,$in,$nin, $mod
$gt:greater than >
$lt:less than <
$gte:greater than or equal to >=
$lte:less than or equal to , >=,$ne:
query.put("competitionStatus", new BasicDBObject("$gt", 0));
// e.g. find all where competitionStatus > 0
? $in,$nin:
List inList = new ArrayList();
inList.add("ATM401101");
inList.add("ATM053101");
query.put("rsc", new BasicDBObject("$in", inList));
// e.g. find all where rsc in (‘ATM401101’,’ ATM053101’)
? $mod特殊写法
按照文档：db.things.find( { a : { $mod : [ 10 , 1 ] } } )
List inList = new ArrayList();
inList.add(12);
inList.add(1);
query.put("competitionStatus", new BasicDBObject("$mod", inList));
这种写法失败，修改为：
System.out.println("-----------华丽分隔线mod---------------");
System.out.println("
SELECT rsc,startDate,startTime, competitionStatus FROM schedule WHERE competitionStatus/12=1
order by startDate asc,startTime asc");
startTime = System.currentTimeMillis();
query = new BasicDBObject();
query.put("$where", "function() { return this.competitionStatus/12
== 1; }");//这种写法成功
field = new BasicDBObject();
field.put("rsc",true);
field.put("startDate",true);
field.put("startTime",true);
field.put("competitionStatus",true);
sort = new BasicDBObject();
sort.put("startDate", 1);
sort.put("startTime", 1);
cur = coll.find(query,field).sort(sort);
System.out.println("查询获得的长度"+cur.count());
System.out.println("查询耗
时:"+(System.currentTimeMillis()-startTime)+"毫秒.");
showAllDataFromCursor(cur);
? $exists
Check for existence (or lack thereof) of a field.
Currently $exists is not able to use an index. Indexes on other fields are still used.
System.out.println("-----------华丽分隔线---------------");
System.out.println("SELECT count(isGold) FROM schedule");
startTime = System.currentTimeMillis();
query = new BasicDBObject();
query.put("isGold", new BasicDBObject("$exists", true));
System.out.println(coll.find(query).count());
System.out.println("查询耗
时:"+(System.currentTimeMillis()-startTime)+"毫秒.");
? $or
System.out.println("-----------华丽分隔线---------------");
System.out.println("
SELECT rsc,startDate,startTime, competitionStatus FROM schedule
WHERE competitionStatus=14 or rsc='ARM102' order by startDate
asc,startTime asc limit 10");
startTime = System.currentTimeMillis();
query = new BasicDBObject();
query.put("$where", "function() { return
this.competitionStatus==14
|| this.rsc=='ARM102'; }");
field = new BasicDBObject();
field.put("rsc",true);
field.put("startDate",true);
field.put("startTime",true);
field.put("competitionStatus",true);
cur = coll.find(query,field).sort(sort).limit(10);
System.out.println("查询获得的长度"+cur.count());
System.out.println("查询耗
时:"+(System.currentTimeMillis()-startTime)+"毫秒.");
showAllDataFromCursor(cur);
? mysql between
System.out.println("-----------华丽分隔线---------------");
System.out.println("SELECT rsc,startDate,startTime FROM schedule
WHERE startDate between '2010-11-15' and '2010-11-17'
order by startDate asc,startTime asc");
startTime = System.currentTimeMillis();
query = new BasicDBObject();
inList = new ArrayList();
inList.add(12);
inList.add(1);
query.put("$where", "function() { return this.startDate
>='2010-11-15' && this.startDate<='2010-11-17';}");
field = new BasicDBObject();
field.put("rsc",true);
field.put("startDate",true);
field.put("startTime",true);
sort = new BasicDBObject();
sort.put("startDate", 1);
sort.put("startTime", 1);
cur = coll.find(query,field).sort(sort).limit(10);
System.out.println("查询获得的长度"+cur.count());
System.out.println("查询耗
时:"+(System.currentTimeMillis()-startTime)+"毫秒.");
showAllDataFromCursor(cur);
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