![]() FROM table: Specify the table from which to get.SELECT columns: Select the columns to return.SELECT columns FROM table WHERE column="value".SELECT word, definition FROM WORD_LIST_TABLE WHERE.For a full description of theĪn SQL query is highly structured. Inserting, deleting, and updating the database. ![]() On Android, the data access object (DAO) provides convenience methods for Retrieving rows that meet given criteria.Very complex, but there are four basic operations: You use the SQL query language to interact with the database. Committing a changelist to the master branch.įor more on transactions, see Atomic Commit In.Entering a term and definition into dictionary.Transferring money from a savings account to a checking account.After a transaction has completed, its effectsĪre permanently in place in the system. Transaction either recognizes data in the state the data was in before anotherĬoncurrent transaction modified it, or the transaction recognizes the data after Must be isolated from modifications made by concurrent transactions. Modifications made by concurrent transactions Transaction must leave all data in a consistent state. Modifications are performed, or none of the modifications are performed.Ītomicity is true even if a program crash, operating-system crash, or powerįailure interrupts the act of writing the change to the disk. To qualify as a transaction, a logical unit of work mustĮxhibit four properties: atomicity, consistency, isolation, and durability To find what's in a specific row, use the _id, or retrieve rowsīy formulating queries that select rows from the table by specifyingĪ transaction is a sequence of operations performed as a single For details of the SQLite database, seeĪfter inserting the words alpha and beta, whereĪlpha has two definitions, the table might look like this: The sourceĬode for SQLite is in the public domain. SQLite is the most widely deployed database engine in the world. Transactional (the changes within a single transaction in SQLite either.Zero-configuration (does not need to be configured for your app).Serverless (requires no server backend).Self-contained (requires no other components).SQLite implements an SQL database engine that has the following Each column is identified by a name that is unique per table.The entity is identified by a unique ID which Fields contain data, references to other fields, or references to other.The intersection of a row and column is called a field.SQL databases store data in tables of rows and columns: This page is a refresher and quick reference. The SQL language used to interact with databases.Android Apps in Kotlin course assumes that you are familiar with the
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