Some fields may be contained within an embedded document. – OK Accessing embedded fields using dotted names
SELECT first_name FROM customers ORDER BY last_name SELECT DISTINCT first_name FROM customers ORDER BY last_name SELECT DISTINCT first_name FROM customers ORDER BY first_nameįirst_name which appears in ORDER BY must also appear in SELECT DISTINCT. When you have a query with DISTINCT and ORDER BY, you can only sort by a selected (visible) field: Technical restrictions to SELECT DISTINCT SELECT DISTINCT first_name, last_name FROM customersįirst names and last names can repeat, but their pairs will not. Note that all the SELECT-ed fields are taken into account. So in a DISTINCT query output, each identical document appears only once. What you get is a list of distinct names: SELECT DISTINCT first_name FROM customers What it returns is a table of names where the names can obviously repeat:īut when you write the query with DISTINCT: SELECT DISTINCT eliminates any repeated documents from the output. With Studio 3T 2019.1, SQL Query now also supports the SELECT DISTINCT clause. This means we can also make use of any mongo operator. The keyword new is optional in data type constructors. You can also use a wide array of mongo data type constructors such as NumberInt, NumberLong, NumberDecimal, ObjectId, ISODate, Date, LUUID, CSUUID, JUUID, PYUUID, UUID, Timestamp, Symbol, DBRef, BinDate, and HexData. As strings, they can be quoted with single-quotes (”) or double-quotes (“”), which means these two queries are the same: JSON can be used in SQL WHERE clauses in two ways: SELECT _id, foo FROM bar JSON objects in WHERE clauses To restore _id and thus make the result editable, we ask for this specific field: Which does not return _id, the result is not editable (no _id means no link to the original document). Pressing ‘Enter’ will write the new value to the database, while pressing ‘Esc’ will return the previous value and exit the editor. To edit a particular field or value in a document, simply double-click on it and a type-specific editor for that value will be activated. That is, rather than having to search for the documents you want to edit and then issue separate UPDATE, DELETE or INSERT commands, you can simply edit the documents directly inline. Edit results inlineĮditing documents and data in the SQL tab in Studio 3T is based on a ‘search and edit’ paradigm. In the screenshot above, only the first query appears underneath the SQL Query tab because it is the SQL statement executed at cursor. It shows the specific query that was actually run, important in the case of a SQL batch that contains multiple queries. The SQL Query tab shows which SQL query was executed by the text cursor (or “at cursor”).
Similar to our IntelliShell, Studio 3T’s built-in mongo shell, SQL Editor detects and suggests standard SQL functions as well as fields, collections, and keyword names. SQL Query also supports smart auto-completion. Hotkey – Press F5 to execute SQL statement at cursor.Right-click – Place the cursor on the desired query, right-click, and choose Execute SQL statement at cursor.Button – Click on the Execute SQL statement marked by the cursor (play) button.You can execute a SQL statement in three ways: This is a silly mistake.Download Studio 3T here and write your own SQL queries as you go through the tutorial.
outside the ETLClass and have it only one-time initialized. It seems this pooling, connection sharing will work only when we use global instance.
Robo 3t run mongo function driver#
I am also thinking if the object creation of ETLClass is making a difference because MongoDB driver reference is in ETLClass. I think that when we create a new instance of MongoClient it will actually create a new connection every time because it is not a static function and the memory, stack allocation will be new. Is there anything to with the subscription for logs which is making it to create separate connection and not disposing of connection due to un-subscription is not being done? Is there any configuration to get an exact error in c# application too. Why is the error different from DCS driver and Robo 3t. Server = new MongoServerAddress(extractURI.Host, extractURI.Port), This.ExtractMongoDBMongoClient = new MongoClient(new MongoClientSettings() Uri extractURI = new Uri(extractMongoDBServerURL) String loadMongoDBServerURL, string loadMongoDBDatabaseName) Public void CreateMongoDBSession(string extractMongoDBServerURL, string extractMongoDBDatabaseName, So there is no timer elapsed events in between ETL to prevent parallel ETL’s. The timer will be disabled when ETL is going on. I have a timer that triggers every 5 seconds and does the migration for a particular date range. The source and target table can be the same in the same database. The database can be in a different MongoDB server. I have a Mongo DB ETL application that will transfer data from one database to another database.
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