api-docs / org.ktorm.expression / SqlExpression

SqlExpression

abstract class SqlExpression (source code)

Root class of SQL expressions or statements.

SQL expressions are tree structures, and can be regarded as SQL abstract syntax trees (AST).

Subclasses must satisfy the following rules:

Must be data class, providing common abilities such as destruction, copy function, equals function, etc.
Must be immutable, any modify operation should return a new expression instance.

To visit or modify expression trees, use SqlExpressionVisitor.

To format expressions as executable SQL strings, use SqlFormatter.

See Also

SqlExpressionVisitor

SqlFormatter

Constructors

Name	Summary
<init>	`SqlExpression()` Root class of SQL expressions or statements.

Properties

Name	Summary
extraProperties	`abstract val extraProperties: Map<String, Any>` Extra properties of this expression, maybe useful in SqlFormatter to generate some special SQLs.
isLeafNode	`abstract val isLeafNode: Boolean` Check if this expression is a leaf node in expression trees.

Extension Properties

Name	Summary
removeBrackets	`val SqlExpression.removeBrackets: Boolean`

Extension Functions

Name	Summary
eq	`infix fun <T : Any> T.eq( expr: ColumnDeclaring<T> ): BinaryExpression<Boolean>` Equal operator, translated to `=` in SQL.
neq	`infix fun <T : Any> T.neq( expr: ColumnDeclaring<T> ): BinaryExpression<Boolean>` Not-equal operator, translated to `<>` in SQL.
notEq	`infix fun <T : Any> T.notEq( expr: ColumnDeclaring<T> ): BinaryExpression<Boolean>` Not-equal operator, translated to `<>` in SQL.

Inheritors

Name	Summary
BulkInsertExpression	`data class BulkInsertExpression : SqlExpression` Bulk insert expression, represents a bulk insert statement in MySQL.
BulkInsertExpression	`data class BulkInsertExpression : SqlExpression` Bulk insert expression, represents a bulk insert statement in PostgreSQL.
BulkInsertExpression	`data class BulkInsertExpression : SqlExpression` Bulk insert expression, represents a bulk insert statement in SQLite.
ColumnAssignmentExpression	`data class ColumnAssignmentExpression<T : Any> : SqlExpression` Column assignment expression, represents a column assignment for insert or update statements.
DeleteExpression	`data class DeleteExpression : SqlExpression` Delete expression, represents the `delete` statement in SQL.
InsertExpression	`data class InsertExpression : SqlExpression` Insert expression, represents the `insert` statement in SQL.
InsertFromQueryExpression	`data class InsertFromQueryExpression : SqlExpression` Insert-from-query expression, eg. `insert into tmp(num) select 1 from dual`.
InsertOrUpdateExpression	`data class InsertOrUpdateExpression : SqlExpression` Insert or update expression, represents an insert statement with an `on duplicate key update` clause in MySQL.
InsertOrUpdateExpression	`data class InsertOrUpdateExpression : SqlExpression` Insert or update expression, represents an insert statement with an `on conflict (key) do update set` clause in PostgreSQL.
InsertOrUpdateExpression	`data class InsertOrUpdateExpression : SqlExpression` Insert or update expression, represents an insert statement with an `on conflict (key) do update set` clause in SQLite.
OrderByExpression	`data class OrderByExpression : SqlExpression` Order-by expression.
QuerySourceExpression	`abstract class QuerySourceExpression : SqlExpression` Query source expression, used in the `from` clause of a SelectExpression.
ScalarExpression	`abstract class ScalarExpression<T : Any> : SqlExpression, ColumnDeclaring<T>` Base class of scalar expressions. An expression is “scalar” if it has a return value (eg. `a + 1`).
UpdateExpression	`data class UpdateExpression : SqlExpression` Update expression, represents the `update` statement in SQL.
WindowFrameBoundExpression	`data class WindowFrameBoundExpression : SqlExpression` Window frame bound expression.
WindowSpecificationExpression	`data class WindowSpecificationExpression : SqlExpression` Window specification expression.