![]() Here is the list of data types in SQLite that you can use to store REAL. SQLite stored real numbers as 8 bytes’ array. REAL numbers are the number with double floating points precision. ![]() The DBCC SHOW_STATISTICS command gives us detailed information about the statistics and dataĭistributions. INTEGER type affinity in SQLite can hold any assigned integer number (positive or negative) from 1 byte to maximum 8 bytes. Create statement for the SQLite table: DROP TABLE event CREATE TABLE event ( id INTEGER PRIMARY KEY, time DATETIME NOT NULL, duration INT NOT NULL, summaryid INT NOT NULL. So that, optimizer estimates how much memory and other resources are required for a query At first I thought maybe this was how the rowID alias was implemented, but once a record is inserted it cannot be fetched using its rowID in the id field. When we create an index this data distribution information is also stored for the NULL valued columns. “How does the SQL Server query optimizer know how many NULL rows are stored for a column in a table?”īasically, the statistics store the data distribution about the tables, and the query optimizer makes use of this information during the creation of a query plan. ![]() Most likely, the following question will pop up in your mind. This situation shows that the query optimizer finds accurate information about how many NULL rows are stored in the The index seek operator details show us there is not any difference between the Actual Number of Rows and the Estimated Number of Rows. Without a doubt, the created index is used by the database engine and it boosts the performance of the query because the logical reads number is lower than the previous one.
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