I have got a avro table (table1) which has 5 fields and all of them are structures with multiple fields (including substructures).
I have another table (table2) which has 3 fields (all structures) and these 3 structures are the same as that of table1
Now have to populate table2 from table 1 and i used the following query
INSERT INTO table2
SELECT struct1, struct2, struct4 FROM table1
But it is not populating the values in table2.
Any idea how can I achieve this?
Copying individual fields is a pain becuase their are nested structures present and struct 1 has got 85 fields, struct2 has 43 fields and struct5 has 78 fields.
Related
I need to create an array with values from another table.
Table 1 has the columns id, A_type, and time
Table 2 has the columns array [{A_type:A_type value, time: time value},...], and id
All the necessary values present in the arrays in Table 2 is available in Table 1.
I need to recreate the array column from Table 2 in Table 1, but I cannot copy the array column from Table 2 due to redundancy issue.
How can I write the query logic so that I can recreate the array in Table 2 using values from Table 1?
Or is it even possible because there are multiple elements in the array?
I tried by simply joining the two tables together by id and create array by matching values from Table 2, but I can't seem to figure out what to do when there are multiple inputs that is made up of json blobs.
I have 2 tables in my SQL database:
And I want to merge them in a way the result will be:
This is just an example for 2 tables which need to be merged into one new table (The tables contain an example data, the statement should work for any amount of data inside the tables).
The ID which got different value in CSV should be updated into the new table for example:
ID 3's value is 'KKK' and in table T is 'CCC', then what should be updated is the CSV table.
You seem to want a left join and to match to the second table if available:
select t.id, coalesce(csv.value, t.value) as value
from t left join
csv
on t.id = csv.id;
If you want this in a new table, use the appropriate construct for your database, or use insert to insert into an existing table.
I have two database tables: TABLE 1 and TABLE 2, both have the same number of columns and have the same columns, the problem is that TABLE 2 has a different order of it columns, So I want to arrange the columns of TABLE 2 like they are arranged in TABL1, but i Dont know how to do that.
I'll be very grateful if you can help me.
Re-create Table2 as create table Table2_Temp as select <sequence of fields like Table1> from Table2. After that re-name tables: Table2 -> Table2_Old (or just drop this one), Table2_Temp -> Table2. This is the simplest way and can be realized in any version of DB.
Change order of columns using non-standard SQL language facilities but if it's possible in using a type of DB.
We have a use case where we have to combine data from 3 tables in redshift.the data size is around 1 million records.
The first table contains client details - tabl1
Second table contains visits - table2 (M2O relation to table1)
table contains events- table3 (M2O relation with table2)
Now we have to aggregate these 3 tables and prepare a record based at the visit level such that it contains the client details from table1, visit details from table2 and all the events attributes of table3.
What is the best way to read data in above format from redshift using batch job?
I have 2 sql tables( A and B) with no relation among them. I wanted to copy the data of one column of table B and merge it with the table A as a new column of able B
How do i do that.
I have tried to write this code -
Insert into TableA(ColumnC) select top 10 ColumnA from TableB