# Database glossary: Apprentice level

52 Database terms at the Apprentice level, each with a short definition and a link to its full page.

Updated: September 28, 2026

[Study these as flash cards](https://www.ask-codey.com/decks/database/apprentice)

- [Aggregate Function](https://www.ask-codey.com/glossary/aggregate-function): A function that summarizes a set of rows into one value.
- [ALTER TABLE](https://www.ask-codey.com/glossary/alter-table): A statement that changes the definition of an existing table.
- [Approximate Numeric Type](https://www.ask-codey.com/glossary/approximate-numeric-type): A floating-point numeric type that may store an approximation of a value.
- [AVG](https://www.ask-codey.com/glossary/avg): An aggregate function returning the average of non-NULL numeric values.
- [BETWEEN Predicate](https://www.ask-codey.com/glossary/between-predicate): A predicate testing whether a value falls within an inclusive lower and upper bound.
- [CASE Expression](https://www.ask-codey.com/glossary/case-expression): An expression that chooses a result by evaluating conditions in order.
- [Character String Type](https://www.ask-codey.com/glossary/character-string-type): A SQL type whose values are sequences of characters.
- [COUNT](https://www.ask-codey.com/glossary/count): An aggregate function returning the number of qualifying rows or non-NULL expression values.
- [CREATE TABLE](https://www.ask-codey.com/glossary/create-table): A statement that defines a new table, its columns, and its constraints.
- [CREATE VIEW](https://www.ask-codey.com/glossary/create-view): A statement that defines a view from a query.
- [CROSS JOIN](https://www.ask-codey.com/glossary/cross-join): A join returning every possible pairing of rows from two table expressions.
- [Data Control Language (DCL)](https://www.ask-codey.com/glossary/data-control-language-dcl): SQL statements that control database privileges and access.
- [Data Definition Language (DDL)](https://www.ask-codey.com/glossary/data-definition-language-ddl): SQL statements that define or change database structures.
- [Data Manipulation Language (DML)](https://www.ask-codey.com/glossary/data-manipulation-language-dml): SQL statements that retrieve or change stored rows.
- [Date and Time Type](https://www.ask-codey.com/glossary/date-and-time-type): A SQL type representing a date, time, timestamp, or interval.
- [DELETE](https://www.ask-codey.com/glossary/delete): A statement that removes selected rows from a table.
- [DROP TABLE](https://www.ask-codey.com/glossary/drop-table): A statement that removes a table definition and its stored data.
- [Exact Numeric Type](https://www.ask-codey.com/glossary/exact-numeric-type): A numeric type representing values with defined precision and scale without binary approximation.
- [EXCEPT](https://www.ask-codey.com/glossary/except): A set operation returning distinct rows in the first result but not the second.
- [EXISTS Predicate](https://www.ask-codey.com/glossary/exists-predicate): A predicate that is true when its subquery returns at least one row.
- [FETCH FIRST](https://www.ask-codey.com/glossary/fetch-first): A standard clause limiting a query result to its first specified number of rows.
- [FULL OUTER JOIN](https://www.ask-codey.com/glossary/full-outer-join): A join returning matched rows plus unmatched rows from both sides.
- [GROUP BY](https://www.ask-codey.com/glossary/group-by): A clause collecting rows with equal grouping values so each group produces one result row.
- [HAVING](https://www.ask-codey.com/glossary/having): A clause filtering groups after grouping and aggregation.
- [IN Predicate](https://www.ask-codey.com/glossary/in-predicate): A predicate testing whether a value equals any value in a list or subquery result.
- [INNER JOIN](https://www.ask-codey.com/glossary/inner-join): A join returning only row combinations that satisfy its join condition.
- [INSERT](https://www.ask-codey.com/glossary/insert): A statement that adds new rows to a table.
- [INTERSECT](https://www.ask-codey.com/glossary/intersect): A set operation returning distinct rows present in both query results.
- [IS NULL Predicate](https://www.ask-codey.com/glossary/is-null-predicate): A predicate testing whether a value is NULL.
- [JOIN](https://www.ask-codey.com/glossary/join-database): A query operation combining related rows from two table expressions.
- [Join Condition](https://www.ask-codey.com/glossary/join-condition): The predicate deciding which rows from joined sources match.
- [LEFT OUTER JOIN](https://www.ask-codey.com/glossary/left-outer-join): A join returning every left row and matching right rows, using NULLs when no right match exists.
- [LIKE Predicate](https://www.ask-codey.com/glossary/like-predicate): A predicate comparing text with a pattern containing wildcard characters.
- [MAX](https://www.ask-codey.com/glossary/max): An aggregate function returning the highest non-NULL value.
- [MIN](https://www.ask-codey.com/glossary/min): An aggregate function returning the lowest non-NULL value.
- [OFFSET Clause](https://www.ask-codey.com/glossary/offset-clause): A clause skipping a specified number of ordered result rows.
- [ON Clause](https://www.ask-codey.com/glossary/on-clause): A join clause containing its match condition.
- [RIGHT OUTER JOIN](https://www.ask-codey.com/glossary/right-outer-join): A join returning every right row and matching left rows, using NULLs when no left match exists.
- [Scalar Subquery](https://www.ask-codey.com/glossary/scalar-subquery): A subquery required to return one column and no more than one row.
- [Self Join](https://www.ask-codey.com/glossary/self-join): A query that joins a table to another reference to the same table.
- [SET Clause](https://www.ask-codey.com/glossary/set-clause): The UPDATE clause assigning new values to columns.
- [Set Operation](https://www.ask-codey.com/glossary/set-operation): An operation combining compatible query results according to set rules.
- [Subquery](https://www.ask-codey.com/glossary/subquery): A query nested inside another SQL statement.
- [SUM](https://www.ask-codey.com/glossary/sum-database): An aggregate function adding the non-NULL numeric values in a group.
- [Table Subquery](https://www.ask-codey.com/glossary/table-subquery): A subquery producing rows and columns that another query can use as a table.
- [Transaction Control Language (TCL)](https://www.ask-codey.com/glossary/transaction-control-language-tcl): SQL statements that complete, reverse, or mark points within transactions.
- [UNION](https://www.ask-codey.com/glossary/union): A set operation combining compatible query results and removing duplicate rows.
- [UNION ALL](https://www.ask-codey.com/glossary/union-all): A set operation combining compatible query results while retaining duplicate rows.
- [UPDATE](https://www.ask-codey.com/glossary/update): A statement that changes values in existing rows.
- [VALUES Clause](https://www.ask-codey.com/glossary/values-clause): A clause that supplies rows of literal or calculated values.
- [View](https://www.ask-codey.com/glossary/view): A named query whose result can be used much like a table.
- [Wildcard Character](https://www.ask-codey.com/glossary/wildcard-character): A pattern character representing unknown text, such as % or \_ with LIKE.

- Previous level: [Novice](https://www.ask-codey.com/glossary/subjects/database/novice)
- Next level: [Journeyman](https://www.ask-codey.com/glossary/subjects/database/journeyman)

[Every Database term, by level](https://www.ask-codey.com/glossary/subjects/database)

Source: https://www.ask-codey.com/glossary/subjects/database/apprentice