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Which of the following is not a component of AWS?
Amazon XPS.
Amazon XPS.
See lessUpdate millions of documents in collections in MongoDB.
On using updateMulti(), it will update all the matching documents in one transaction. It is more efficient than updating the files one by one, as it decreases the network round-trips across the DB and the application .
On using
See lessupdateMulti()
, it will update all the matching documents in one transaction. It is more efficient than updating the files one by one, as it decreases the network round-trips across the DB and the application .What happens if you cast a spark dataframe as a glue dynamic frame and vice versa?
You can shift between the AWS Glue ETL service and Apache Spark easily by casting a Glue DynamicFrame as a Spark DataFrame, or vice versa. This allows you to take advantage of each platform's features based on on your individual requirements and scenarios.
You can shift between the AWS Glue ETL service and Apache Spark easily by casting a Glue DynamicFrame as a Spark DataFrame, or vice versa. This allows you to take advantage of each platform’s features based on on your individual requirements and scenarios.
See lessWhat is a Datum data type in PostgreSQL?
In layman's terms, it's a type of data saved in a database. Working with SQL queries on a PostgreSQL database allows you to deal with Datums indirectly using SQL queries and data manipulation tools. Within tables, you may do actions on them such as selecting, inserting, updating, or deleting.
In layman’s terms, it’s a type of data saved in a database. Working with SQL queries on a PostgreSQL database allows you to deal with Datums indirectly using SQL queries and data manipulation tools. Within tables, you may do actions on them such as selecting, inserting, updating, or deleting.
See lessJoin two tables in MongoDB.
db.Employee.aggregate([ { $match: { country: "Germany" }}, { $lookup: { from: "Department", let: { deptid: { "$toObjectId": "$deptid" }}, pipeline: [ { $match: { deptname: { $in: ["IT","HR"]}, $expr: { $eq: ["$_id", "$$deptid"] }}}], as: "Department" }}, { $unwind: "$Department" }]) You can use corrRead more
You can use correlated subquery if deptid is an ObjectId.
See lessHow to perform data migration in PostgreSQL?
dump the source db: pg_dump -U username -F create the target db: createdb -U username targetdb restore the dump file to target db: psql -U username targetdb < sourcedb_dump.sql
dump the source db:
pg_dump -U username -F
create the target db:
createdb -U username targetdb
restore the dump file to target db:
See lesspsql -U username targetdb < sourcedb_dump.sql
Getting NULL values when loading data from excel in Pyspark.
Date format expression will be, to_date('1899-12-30', 'y-M-d') not yyyy-MM-dd.
Date format expression will be,
to_date('1899-12-30', 'y-M-d')
not
See lessyyyy-MM-dd
.