What is query and non query?
Emily Sparks What is query and non query?
ExecuteNonQuery: Executes Insert, Update, and Delete statements (DML statements) and returns the number of rows affected. ExecuteReader: Executes the SQL query (Select statement) and returns a Reader object which can perform a forward only traversal across the set of records being fetched.
What is difference between execute and non query?
ExecuteReader() returns an object that can iterate over the entire result set while only keeping one record in memory at a time. ExecuteNonQuery() does not return data at all: only the number of rows affected by an insert, update, or delete.
What is the use of execute non query?
ExecuteNonQuery used for executing queries that does not return any data. It is used to execute the sql statements like update, insert, delete etc. ExecuteNonQuery executes the command and returns the number of rows affected.
What is difference between ExecuteReader and ExecuteNonQuery?
ExecuteReader is used for any result set with multiple rows/columns (e.g., SELECT col1, col2 from sometable ). ExecuteNonQuery is typically used for SQL statements without results (e.g., UPDATE, INSERT, etc.).
Which is faster DataReader or DataAdapter?
Using a DataReader produces faster results than using a DataAdapter to return the same data. Because the DataAdapter actually uses a DataReader to retrieve data, this should not surprise us.
What is dataset and DataReader?
Dataset is used to hold tables with data. DataReader is designed to retrieve a read-only, forward-only stream of data from data sources. DataReader has a connection oriented nature, whenever you want fetch the data from database that you must have a connection.
What is the difference between ExecuteScalar and ExecuteNonQuery?
ExecuteScalar() only returns the value from the first column of the first row of your query. ExecuteReader() returns an object that can iterate over the entire result set. ExecuteNonQuery() does not return data at all: only the number of rows affected by an insert, update, or delete.
What is DataSet and DataReader?
What is ExecuteScalar and ExecuteNonQuery?
What is DataReader and DataAdapter?
DataAdapter is an intermediate layer/ middleware which acts a bridge between the DataSet and a Database whereas DataReader provides forward-only, read-only access to data using a server-side cursor (simply put it is ued to read the data).
When should I use DataReader and DataAdapter?
Using the DataReader can increase application performance both by retrieving data as soon as it is available, and (by default) storing only one row at a time in memory, reducing system overhead. A DataAdapter is used to retrieve data from a data source and populate tables within a DataSet.
Why is DataReader useful?
The DataReader provides an unbuffered stream of data that allows procedural logic to efficiently process results from a data source sequentially. The DataReader is a good choice when retrieving large amounts of data because the data is not cached in memory.
What is execute non query in SQL Server?
Execute Non Query is ADO.Net Object it is used for execute SQL Statement for Insert,Update Delete, and it does not return any value It is use to excute the command which returns no record like our insert,update and delete opration.
What is executenonquery command in SQL Server?
ExecuteNonQuery used for executing queries that does not return any data. It is used to execute the sql statements like update, insert, delete etc. ExecuteNonQuery executes the command and returns the number of rows affected. ##will work with Action Queries only (Create,Alter,Drop,Insert,Update,Delete).
What is the difference between SQL and NoSQL?
SQL databases are vertically scalable while NoSQL databases are horizontally scalable. SQL databases have a predefined schema whereas NoSQL databases use dynamic schema for unstructured data. Comparing NoSQL vs SQL performance, SQL requires specialized DB hardware for better performance while NoSQL uses commodity hardware.
What is Structured Query Language (SQL)?
A SQL database supports structured query language (SQL) — a domain-specific programming language for querying and manipulating data in a relational database. The key to the relational model is abstracting data as a set of tuples organized into “relations,” which allows for abstraction over the physical representation of data and access paths.