mongodb find rewrite

mongodb find 查询转换与重写，在语义和实际结果相同的前提下，实现

文章目录

mongodb find rewritewrite 1find coderesultexplain write 2find coderesultexplain write 3find coderesultexplain

write 1

find code

db.inventory.find({$and:[{qty:{$gt:50,$lt:100,$type:1}}]})

result

explain

> db.inventory.find({$and:[{qty:{$gt:50,$lt:100,$type:1}}]}).explain() { "queryPlanner" : { "plannerVersion" : 1, "namespace" : "inventory.inventory", "indexFilterSet" : false, "parsedQuery" : { "$and" : [ { "qty" : { "$lt" : 100 } }, { "qty" : { "$gt" : 50 } }, { "qty" : { "$type" : [ 1 ] } } ] }, "queryHash" : "F8D429A6", "planCacheKey" : "F8D429A6", "winningPlan" : { "stage" : "COLLSCAN", "filter" : { "$and" : [ { "qty" : { "$lt" : 100 } }, { "qty" : { "$gt" : 50 } }, { "qty" : { "$type" : [ 1 ] } } ] }, "direction" : "forward" }, "rejectedPlans" : [ ] }, "serverInfo" : { "host" : "node2", "port" : 27017, "version" : "4.2.7", "gitVersion" : "51d9fe12b5d19720e72dcd7db0f2f17dd9a19212" }, "ok" : 1 }

write 2

find code

db.inventory.find({qty:{$gt:50,$lt:100,$type:1}})

result

explain

> db.inventory.find({qty:{$gt:50,$lt:100,$type:1}}).explain() { "queryPlanner" : { "plannerVersion" : 1, "namespace" : "inventory.inventory", "indexFilterSet" : false, "parsedQuery" : { "$and" : [ { "qty" : { "$lt" : 100 } }, { "qty" : { "$gt" : 50 } }, { "qty" : { "$type" : [ 1 ] } } ] }, "queryHash" : "F8D429A6", "planCacheKey" : "F8D429A6", "winningPlan" : { "stage" : "COLLSCAN", "filter" : { "$and" : [ { "qty" : { "$lt" : 100 } }, { "qty" : { "$gt" : 50 } }, { "qty" : { "$type" : [ 1 ] } } ] }, "direction" : "forward" }, "rejectedPlans" : [ ] }, "serverInfo" : { "host" : "node2", "port" : 27017, "version" : "4.2.7", "gitVersion" : "51d9fe12b5d19720e72dcd7db0f2f17dd9a19212" }, "ok" : 1 }

write 3

find code

db.inventory.find({$and:[{qty:{$gt:50}},{qty:{$lt:100}},{qty:{$type:1}}]})

result

explain

> db.inventory.find({$and:[{qty:{$gt:50}},{qty:{$lt:100}},{qty:{$type:1}}]}).explain() { "queryPlanner" : { "plannerVersion" : 1, "namespace" : "inventory.inventory", "indexFilterSet" : false, "parsedQuery" : { "$and" : [ { "qty" : { "$lt" : 100 } }, { "qty" : { "$gt" : 50 } }, { "qty" : { "$type" : [ 1 ] } } ] }, "queryHash" : "F8D429A6", "planCacheKey" : "F8D429A6", "winningPlan" : { "stage" : "COLLSCAN", "filter" : { "$and" : [ { "qty" : { "$lt" : 100 } }, { "qty" : { "$gt" : 50 } }, { "qty" : { "$type" : [ 1 ] } } ] }, "direction" : "forward" }, "rejectedPlans" : [ ] }, "serverInfo" : { "host" : "node2", "port" : 27017, "version" : "4.2.7", "gitVersion" : "51d9fe12b5d19720e72dcd7db0f2f17dd9a19212" }, "ok" : 1 }