Join three table using library knex.js
I am using knex.js
suppose we have three table :-
table1-- id,name,address
table2--id,city,sate,table1_id as fk
table3--id,housenumber,table1_id as fk
I want to join these three table using knex.js libraray of node and express
so that i want to get output json like this.
{
"id":1,
"name":"abc",
"address:"xyz",
"table2":{"id":1,"city":"ttt","state":"www" }//i want check if table1.id == table2.table1_id then put table details
"table3"://if no relation found between table1.id === table3.table1.id then kept it as an array
}
node.js express knex.js
asked Nov 19 '18 at 15:38
Amit KumarAmit Kumar
85
add a comment |
I am using knex.js
suppose we have three table :-
table1-- id,name,address
table2--id,city,sate,table1_id as fk
table3--id,housenumber,table1_id as fk
I want to join these three table using knex.js libraray of node and express
so that i want to get output json like this.
{
"id":1,
"name":"abc",
"address:"xyz",
"table2":{"id":1,"city":"ttt","state":"www" }//i want check if table1.id == table2.table1_id then put table details
"table3"://if no relation found between table1.id === table3.table1.id then kept it as an array
}
node.js express knex.js
asked Nov 19 '18 at 15:38
Amit KumarAmit Kumar
85
add a comment |
I am using knex.js
suppose we have three table :-
table1-- id,name,address
table2--id,city,sate,table1_id as fk
table3--id,housenumber,table1_id as fk
I want to join these three table using knex.js libraray of node and express
so that i want to get output json like this.
{
"id":1,
"name":"abc",
"address:"xyz",
"table2":{"id":1,"city":"ttt","state":"www" }//i want check if table1.id == table2.table1_id then put table details
"table3"://if no relation found between table1.id === table3.table1.id then kept it as an array
}
node.js express knex.js
asked Nov 19 '18 at 15:38
Amit KumarAmit Kumar
85
I am using knex.js
suppose we have three table :-
table1-- id,name,address
table2--id,city,sate,table1_id as fk
table3--id,housenumber,table1_id as fk
I want to join these three table using knex.js libraray of node and express
so that i want to get output json like this.
{
"id":1,
"name":"abc",
"address:"xyz",
"table2":{"id":1,"city":"ttt","state":"www" }//i want check if table1.id == table2.table1_id then put table details
"table3"://if no relation found between table1.id === table3.table1.id then kept it as an array
}
node.js express knex.js
node.js express knex.js
asked Nov 19 '18 at 15:38
Amit KumarAmit Kumar
85
asked Nov 19 '18 at 15:38
Amit KumarAmit Kumar
85
asked Nov 19 '18 at 15:38
Amit KumarAmit Kumar
85
asked Nov 19 '18 at 15:38
Amit KumarAmit Kumar
85
asked Nov 19 '18 at 15:38
Amit KumarAmit Kumar
85
85
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
tl;dr knex is too low level tool for the thing you are trying to do, you should use an ORM for that kind of task
However you can do that with lots of manual work.
First you have to make the query with proper joins and creating aliases with table prefixes for each column of table to be able to get result data in a format where all data is in a flat array like:
knex('table1' as t1)
.join('table2 as t2', 't2.t1_id', 't1.id')
.select(
't1.id as t1_id',
't1.other_column as t1_other_column',
't2.id as t2_id', <more columns you want to extract>)
Results something like
[ { t1_id: 1, t1_other_column: 'foo', t2_id: 4}, ... more rows with flat data... }]
Then you need to write javascript code for restructuring flat data to nested objects.
But you should not do that kind of work manually. All knex based ORMs has already implemented general solutions for writing that kind of queries in easy manner.
answered Nov 20 '18 at 10:08
Mikael LepistöMikael Lepistö
7,15912728
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
tl;dr knex is too low level tool for the thing you are trying to do, you should use an ORM for that kind of task
However you can do that with lots of manual work.
First you have to make the query with proper joins and creating aliases with table prefixes for each column of table to be able to get result data in a format where all data is in a flat array like:
knex('table1' as t1)
.join('table2 as t2', 't2.t1_id', 't1.id')
.select(
't1.id as t1_id',
't1.other_column as t1_other_column',
't2.id as t2_id', <more columns you want to extract>)
Results something like
[ { t1_id: 1, t1_other_column: 'foo', t2_id: 4}, ... more rows with flat data... }]
Then you need to write javascript code for restructuring flat data to nested objects.
But you should not do that kind of work manually. All knex based ORMs has already implemented general solutions for writing that kind of queries in easy manner.
answered Nov 20 '18 at 10:08
Mikael LepistöMikael Lepistö
7,15912728
add a comment |
tl;dr knex is too low level tool for the thing you are trying to do, you should use an ORM for that kind of task
However you can do that with lots of manual work.
First you have to make the query with proper joins and creating aliases with table prefixes for each column of table to be able to get result data in a format where all data is in a flat array like:
knex('table1' as t1)
.join('table2 as t2', 't2.t1_id', 't1.id')
.select(
't1.id as t1_id',
't1.other_column as t1_other_column',
't2.id as t2_id', <more columns you want to extract>)
Results something like
[ { t1_id: 1, t1_other_column: 'foo', t2_id: 4}, ... more rows with flat data... }]
Then you need to write javascript code for restructuring flat data to nested objects.
But you should not do that kind of work manually. All knex based ORMs has already implemented general solutions for writing that kind of queries in easy manner.
answered Nov 20 '18 at 10:08
Mikael LepistöMikael Lepistö
7,15912728
add a comment |
tl;dr knex is too low level tool for the thing you are trying to do, you should use an ORM for that kind of task
However you can do that with lots of manual work.
First you have to make the query with proper joins and creating aliases with table prefixes for each column of table to be able to get result data in a format where all data is in a flat array like:
knex('table1' as t1)
.join('table2 as t2', 't2.t1_id', 't1.id')
.select(
't1.id as t1_id',
't1.other_column as t1_other_column',
't2.id as t2_id', <more columns you want to extract>)
Results something like
[ { t1_id: 1, t1_other_column: 'foo', t2_id: 4}, ... more rows with flat data... }]
Then you need to write javascript code for restructuring flat data to nested objects.
But you should not do that kind of work manually. All knex based ORMs has already implemented general solutions for writing that kind of queries in easy manner.
answered Nov 20 '18 at 10:08
Mikael LepistöMikael Lepistö
7,15912728
tl;dr knex is too low level tool for the thing you are trying to do, you should use an ORM for that kind of task
However you can do that with lots of manual work.
First you have to make the query with proper joins and creating aliases with table prefixes for each column of table to be able to get result data in a format where all data is in a flat array like:
knex('table1' as t1)
.join('table2 as t2', 't2.t1_id', 't1.id')
.select(
't1.id as t1_id',
't1.other_column as t1_other_column',
't2.id as t2_id', <more columns you want to extract>)
Results something like
[ { t1_id: 1, t1_other_column: 'foo', t2_id: 4}, ... more rows with flat data... }]
Then you need to write javascript code for restructuring flat data to nested objects.
But you should not do that kind of work manually. All knex based ORMs has already implemented general solutions for writing that kind of queries in easy manner.
answered Nov 20 '18 at 10:08
Mikael LepistöMikael Lepistö
7,15912728
answered Nov 20 '18 at 10:08
Mikael LepistöMikael Lepistö
7,15912728
answered Nov 20 '18 at 10:08
Mikael LepistöMikael Lepistö
7,15912728
answered Nov 20 '18 at 10:08
Mikael LepistöMikael Lepistö
7,15912728
7,15912728
add a comment |
add a comment |
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