SelectStatement (DataNucleus RDBMS plugin 5.1.12-SNAPSHOT API)

java.lang.Object
- org.datanucleus.store.rdbms.sql.SQLStatement
- - org.datanucleus.store.rdbms.sql.SelectStatement

public class SelectStatement
extends SQLStatement

SQL SELECT Statement representation. This will create a statement like

 SELECT {expr}, {expr}, ...
 FROM {tblExpr} [joinInfo {tblExpr} ON ...] ...
 WHERE {boolExpr} [AND|OR] {boolExpr} ...
 GROUP BY {expr}, {expr}
 HAVING {boolExpr}
 ORDER BY {expr} [ASC|DESC], {expr} [ASC|DESC], ...

and also supports UNIONs between SQLStatements, and having sub-queries of other SQLStatements.

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

protected class SelectStatement.SelectedItem

Nested Classes
Modifier and Type	Class and Description
`protected class`	`SelectStatement.SelectedItem`

Field Summary

Fields
Modifier and Type	Field and Description
`protected boolean`	`aggregated` whether there is an aggregate expression present in the select
`protected boolean`	`allowUnions` Whether to make use of any UNIONs on this statement (for when we just want to use this statement on its own).
`protected boolean`	`distinct` Whether the statement is distinct.
`protected List<SQLExpression>`	`groupingExpressions` Expression(s) for the GROUP BY clause.
`protected BooleanExpression`	`having` Having clause.
`protected boolean[]`	`orderingDirections` Directions for any ORDER BY expressions (1 for each orderingExpressions entry).
`protected SQLExpression[]`	`orderingExpressions` Expressions for any ORDER BY clause.
`protected org.datanucleus.query.NullOrderingType[]`	`orderNullDirectives` Directives for null handling of any ORDER BY expressions (1 for each orderingExpressions entry).
`protected long`	`rangeCount` The number of records to be retrieved in any range restriction.
`protected long`	`rangeOffset` The offset for any range restriction.
`protected List<SelectStatement.SelectedItem>`	`selectedItems` List of selected items, including any alias to use.
`protected List<SelectStatement>`	`unions` List of unioned SelectStatements (if any).

Fields inherited from class org.datanucleus.store.rdbms.sql.SQLStatement
candidateClassName, clr, EXTENSION_LOCK_FOR_UPDATE, EXTENSION_LOCK_FOR_UPDATE_NOWAIT, EXTENSION_SQL_TABLE_NAMING_STRATEGY, extensions, joins, namer, parent, primaryTable, queryGenerator, rdbmsMgr, requiresJoinReorder, sql, tableGroups, tableNamerByName, tables, where

Constructor Summary

Constructors
Constructor and Description
`SelectStatement(RDBMSStoreManager rdbmsMgr, Table table, DatastoreIdentifier alias, String tableGroupName)` Constructor for a SELECT statement.
`SelectStatement(RDBMSStoreManager rdbmsMgr, Table table, DatastoreIdentifier alias, String tableGroupName, Map<String,Object> extensions)` Constructor for a SELECT statement.
`SelectStatement(SQLStatement parentStmt, RDBMSStoreManager rdbmsMgr, Table table, DatastoreIdentifier alias, String tableGroupName)` Constructor for a SELECT statement, maybe as a subquery.
`SelectStatement(SQLStatement parentStmt, RDBMSStoreManager rdbmsMgr, Table table, DatastoreIdentifier alias, String tableGroupName, Map<String,Object> extensions)` Constructor for a SELECT statement, maybe as a subquery.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`addAndConditionToJoinForTable(SQLTable sqlTbl, BooleanExpression andCondition, boolean applyToUnions)` Method to find the JOIN for the specified table and add the specified 'and' condition to the JOIN as an 'ON' clause.
`void`	`addGroupingExpression(SQLExpression expr)` Method to add a grouping expression to the query.
`protected void`	`addOrderComponent(SQLText orderST, String orderString, SQLExpression orderExpr, boolean orderDirection, org.datanucleus.query.NullOrderingType orderNullDirective, DatastoreAdapter dba)`
`protected void`	`addOrderingColumnsToSelect()` Convenience method to add any necessary columns to the SELECT that are needed by the ordering constraint.
`boolean`	`allUnionsForSamePrimaryTable()` Convenience accessor for whether all unions of this statement are for the same primary table.
`protected SQLText`	`generateOrderingStatement()` Convenience method to generate the ordering statement to add to the overall query statement.
`int`	`getNumberOfSelects()` Accessor for the number of selected items in the SELECT clause.
`int`	`getNumberOfUnions()`
`protected SQLText`	`getSqlForJoins(boolean lock)` Convenience method to return the JOIN clause implied by the "joins" List.
`SQLText`	`getSQLText()`
`List<SelectStatement>`	`getUnions()` Accessor for the unioned statements.
`boolean`	`isDistinct()` Accessor for whether the statement restricts the results to distinct.
`SQLTable`	`join(SQLJoin.JoinType joinType, SQLTable sourceTable, JavaTypeMapping sourceMapping, JavaTypeMapping sourceParentMapping, Table target, String targetAlias, JavaTypeMapping targetMapping, JavaTypeMapping targetParentMapping, Object[] discrimValues, String tableGrpName, boolean applyToUnions, SQLJoin parentJoin)` Method to form a join to the specified table using the provided mappings, with the join condition derived from the source-target mappings.
`SQLTable`	`join(SQLJoin.JoinType joinType, SQLTable sourceTable, Table target, String targetAlias, String tableGrpName, BooleanExpression joinCondition, boolean applyToUnions)` Method to form a join to the specified table using the provided mappings and applying the provided join condition (rather than generating one from the source/target mappings).
`String`	`removeCrossJoin(SQLTable targetSqlTbl)` Method to remove a cross join for the specified table (if joined via cross join).
`int[]`	`select(SQLExpression expr, String alias)` Select an expression.
`int`	`select(SQLTable table, Column column, String alias)` Add a select clause for the specified column.
`int[]`	`select(SQLTable table, JavaTypeMapping mapping, String alias)` Add a select clause for the specified field (via its mapping) and apply to unions.
`int[]`	`select(SQLTable table, JavaTypeMapping mapping, String alias, boolean applyToUnions)` Add a select clause for the specified field (via its mapping).
`protected int`	`selectItem(SQLText st, String alias, boolean primary)` Internal method to find the position of an item in the select list and return the position if found (first position is 1).
`void`	`setAllowUnions(boolean flag)`
`void`	`setDistinct(boolean distinct)` Mutator for whether the query returns distinct results.
`void`	`setHaving(BooleanExpression expr)` Mutator for the "having" expression.
`void`	`setOrdering(SQLExpression[] exprs, boolean[] descending)` Mutator for the ordering criteria.
`void`	`setOrdering(SQLExpression[] exprs, boolean[] descending, org.datanucleus.query.NullOrderingType[] nullOrders)` Mutator for the ordering criteria.
`void`	`setRange(long offset, long count)` Method to add a range constraint on any SELECT.
`void`	`union(SelectStatement stmt)` Method to union this SQL statement with another SQL statement.
`void`	`whereAnd(BooleanExpression expr, boolean applyToUnions)` Method to add an AND condition to the WHERE clause.
`void`	`whereOr(BooleanExpression expr, boolean applyToUnions)` Method to add an OR condition to the WHERE clause.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - allowUnions
```
protected boolean allowUnions
```
    Whether to make use of any UNIONs on this statement (for when we just want to use this statement on its own).
  - unions
```
protected List<SelectStatement> unions
```
    List of unioned SelectStatements (if any).
  - distinct
```
protected boolean distinct
```
    Whether the statement is distinct.
  - selectedItems
```
protected List<SelectStatement.SelectedItem> selectedItems
```
    List of selected items, including any alias to use.
  - aggregated
```
protected boolean aggregated
```
    whether there is an aggregate expression present in the select
  - groupingExpressions
```
protected List<SQLExpression> groupingExpressions
```
    Expression(s) for the GROUP BY clause.
  - having
```
protected BooleanExpression having
```
    Having clause.
  - orderingExpressions
```
protected SQLExpression[] orderingExpressions
```
    Expressions for any ORDER BY clause.
  - orderingDirections
```
protected boolean[] orderingDirections
```
    Directions for any ORDER BY expressions (1 for each orderingExpressions entry).
  - orderNullDirectives
```
protected org.datanucleus.query.NullOrderingType[] orderNullDirectives
```
    Directives for null handling of any ORDER BY expressions (1 for each orderingExpressions entry).
  - rangeOffset
```
protected long rangeOffset
```
    The offset for any range restriction.
  - rangeCount
```
protected long rangeCount
```
    The number of records to be retrieved in any range restriction.
- Constructor Detail
  - SelectStatement
```
public SelectStatement(RDBMSStoreManager rdbmsMgr,
                       Table table,
                       DatastoreIdentifier alias,
                       String tableGroupName)
```
    Constructor for a SELECT statement.
    
    Parameters:
    
    rdbmsMgr - Store Manager
    
    table - The primary table to DELETE
    
    alias - Alias for the primary table
    
    tableGroupName - Group name for the primary table
  - SelectStatement
```
public SelectStatement(RDBMSStoreManager rdbmsMgr,
                       Table table,
                       DatastoreIdentifier alias,
                       String tableGroupName,
                       Map<String,Object> extensions)
```
    Constructor for a SELECT statement.
    
    Parameters:
    
    rdbmsMgr - Store Manager
    
    table - The primary table to DELETE
    
    alias - Alias for the primary table
    
    tableGroupName - Group name for the primary table
    
    extensions - Any extensions (optional)
  - SelectStatement
```
public SelectStatement(SQLStatement parentStmt,
                       RDBMSStoreManager rdbmsMgr,
                       Table table,
                       DatastoreIdentifier alias,
                       String tableGroupName)
```
    Constructor for a SELECT statement, maybe as a subquery.
    
    Parameters:
    
    parentStmt - Parent statement when this is a subquery SELECT.
    
    rdbmsMgr - Store Manager
    
    table - The primary table to DELETE
    
    alias - Alias for the primary table
    
    tableGroupName - Group name for the primary table
  - SelectStatement
```
public SelectStatement(SQLStatement parentStmt,
                       RDBMSStoreManager rdbmsMgr,
                       Table table,
                       DatastoreIdentifier alias,
                       String tableGroupName,
                       Map<String,Object> extensions)
```
    Constructor for a SELECT statement, maybe as a subquery.
    
    Parameters:
    
    parentStmt - Parent statement when this is a subquery SELECT.
    
    rdbmsMgr - Store Manager
    
    table - The primary table to DELETE
    
    alias - Alias for the primary table
    
    tableGroupName - Group name for the primary table
    
    extensions - Any extensions (optional)
- Method Detail
  - isDistinct
```
public boolean isDistinct()
```
    Accessor for whether the statement restricts the results to distinct.
    
    Returns:
    
    Whether results are distinct
  - setDistinct
```
public void setDistinct(boolean distinct)
```
    Mutator for whether the query returns distinct results.
    
    Parameters:
    
    distinct - Whether to return distinct
  - getNumberOfSelects
```
public int getNumberOfSelects()
```
    Accessor for the number of selected items in the SELECT clause.
    
    Returns:
    
    Number of selected items
  - select
```
public int[] select(SQLExpression expr,
                    String alias)
```
    Select an expression. This will be used when adding aggregates to the select clause (e.g "COUNT(*)").
    
    Parameters:
    
    expr - The expression to add to the select statement
    
    alias - Optional alias for this selected expression
    
    Returns:
    
    The index(es) of the expression in the select
  - select
```
public int[] select(SQLTable table,
                    JavaTypeMapping mapping,
                    String alias,
                    boolean applyToUnions)
```
    Add a select clause for the specified field (via its mapping). If an alias is supplied and there are more than 1 column for this mapping then they will have names like "{alias}_n" where n is the column number (starting at 0).
    
    Parameters:
    
    table - The SQLTable to select from (null implies the primary table)
    
    mapping - The mapping for the field
    
    alias - optional alias
    
    applyToUnions - Whether to apply to unions
    
    Returns:
    
    The column index(es) in the statement for the specified field (1 is first).
  - select
```
public int[] select(SQLTable table,
                    JavaTypeMapping mapping,
                    String alias)
```
    Add a select clause for the specified field (via its mapping) and apply to unions. If an alias is supplied and there are more than 1 column for this mapping then they will have names like "{alias}_n" where n is the column number (starting at 0).
    
    Parameters:
    
    table - The SQLTable to select from (null implies the primary table)
    
    mapping - The mapping for the field
    
    alias - optional alias
    
    Returns:
    
    The column index(es) in the statement for the specified field (1 is first).
  - select
```
public int select(SQLTable table,
                  Column column,
                  String alias)
```
    Add a select clause for the specified column.
    
    Parameters:
    
    table - The SQLTable to select from (null implies the primary table)
    
    column - The column
    
    alias - Optional alias
    
    Returns:
    
    The column index in the statement for the specified column (1 is first).
  - selectItem
```
protected int selectItem(SQLText st,
                         String alias,
                         boolean primary)
```
    Internal method to find the position of an item in the select list and return the position if found (first position is 1). If the item is not found then it is added and the new position returned.
    
    Parameters:
    
    st - SQLText for this selected item
    
    alias - Any alias (optional)
    
    primary - Whether this selected item is a primary component (i.e column)
    
    Returns:
    
    Position in the selectedItems list (first position is 1)
  - addAndConditionToJoinForTable
```
public void addAndConditionToJoinForTable(SQLTable sqlTbl,
                                          BooleanExpression andCondition,
                                          boolean applyToUnions)
```
    Method to find the JOIN for the specified table and add the specified 'and' condition to the JOIN as an 'ON' clause.
    
    Overrides:
    
    addAndConditionToJoinForTable in class SQLStatement
    
    Parameters:
    
    sqlTbl - The table
    
    andCondition - The 'ON' condition to add
    
    applyToUnions - Whether to apply to unions (see SelectStatement)
  - addGroupingExpression
```
public void addGroupingExpression(SQLExpression expr)
```
    Method to add a grouping expression to the query. Adds the grouping to any unioned queries
    
    Parameters:
    
    expr - The expression
  - setHaving
```
public void setHaving(BooleanExpression expr)
```
    Mutator for the "having" expression.
    
    Parameters:
    
    expr - Boolean expression for the having clause
  - setOrdering
```
public void setOrdering(SQLExpression[] exprs,
                        boolean[] descending)
```
    Mutator for the ordering criteria.
    
    Parameters:
    
    exprs - The expressions to order by
    
    descending - Whether each expression is ascending/descending
  - setOrdering
```
public void setOrdering(SQLExpression[] exprs,
                        boolean[] descending,
                        org.datanucleus.query.NullOrderingType[] nullOrders)
```
    Mutator for the ordering criteria.
    
    Parameters:
    
    exprs - The expressions to order by
    
    descending - Whether each expression is ascending/descending
    
    nullOrders - Ordering for nulls (if provided)
  - setRange
```
public void setRange(long offset,
                     long count)
```
    Method to add a range constraint on any SELECT. This typically will use LIMIT/OFFSET where they are supported by the underlying RDBMS.
    
    Parameters:
    
    offset - The offset to start from
    
    count - The number of records to return
  - getSQLText
```
public SQLText getSQLText()
```
    Overrides:
    
    getSQLText in class SQLStatement
  - getSqlForJoins
```
protected SQLText getSqlForJoins(boolean lock)
```
    Convenience method to return the JOIN clause implied by the "joins" List.
    
    Parameters:
    
    lock - Whether to add locking on the join clause (only for some RDBMS)
    
    Returns:
    
    The SQL for the join clause
  - generateOrderingStatement
```
protected SQLText generateOrderingStatement()
```
    Convenience method to generate the ordering statement to add to the overall query statement.
    
    Returns:
    
    The ordering statement
  - addOrderComponent
```
protected void addOrderComponent(SQLText orderST,
                                 String orderString,
                                 SQLExpression orderExpr,
                                 boolean orderDirection,
                                 org.datanucleus.query.NullOrderingType orderNullDirective,
                                 DatastoreAdapter dba)
```
  - addOrderingColumnsToSelect
```
protected void addOrderingColumnsToSelect()
```
    Convenience method to add any necessary columns to the SELECT that are needed by the ordering constraint.
  - setAllowUnions
```
public void setAllowUnions(boolean flag)
```
  - getNumberOfUnions
```
public int getNumberOfUnions()
```
  - getUnions
```
public List<SelectStatement> getUnions()
```
    Accessor for the unioned statements.
    
    Returns:
    
    The unioned SQLStatements
  - union
```
public void union(SelectStatement stmt)
```
    Method to union this SQL statement with another SQL statement.
    
    Parameters:
    
    stmt - The other SQL statement to union
  - allUnionsForSamePrimaryTable
```
public boolean allUnionsForSamePrimaryTable()
```
    Convenience accessor for whether all unions of this statement are for the same primary table.
    
    Returns:
    
    Whether all unions have the same primary table
  - join
```
public SQLTable join(SQLJoin.JoinType joinType,
                     SQLTable sourceTable,
                     JavaTypeMapping sourceMapping,
                     JavaTypeMapping sourceParentMapping,
                     Table target,
                     String targetAlias,
                     JavaTypeMapping targetMapping,
                     JavaTypeMapping targetParentMapping,
                     Object[] discrimValues,
                     String tableGrpName,
                     boolean applyToUnions,
                     SQLJoin parentJoin)
```
    Description copied from class: SQLStatement
    
    Method to form a join to the specified table using the provided mappings, with the join condition derived from the source-target mappings.
    
    Overrides:
    
    join in class SQLStatement
    
    Parameters:
    
    joinType - Type of join.
    
    sourceTable - SQLTable for the source (null implies primaryTable)
    
    sourceMapping - Mapping in this table to join from
    
    sourceParentMapping - Optional, if this source mapping is a sub mapping (e.g interface impl).
    
    target - Table to join to
    
    targetAlias - Alias for the target table (if known)
    
    targetMapping - Mapping in the other table to join to (also defines the table to join to)
    
    targetParentMapping - Optional, if this source mapping is a sub mapping (e.g interface impl).
    
    discrimValues - Any discriminator values to apply for the joined table (null if not)
    
    tableGrpName - Name of the table group for the target (null implies a new group)
    
    applyToUnions - Whether to apply to any unioned statements (only applies to SELECT statements)
    
    parentJoin - Parent join when this join will be a sub-join (part of "join grouping")
    
    Returns:
    
    SQLTable for the target
  - join
```
public SQLTable join(SQLJoin.JoinType joinType,
                     SQLTable sourceTable,
                     Table target,
                     String targetAlias,
                     String tableGrpName,
                     BooleanExpression joinCondition,
                     boolean applyToUnions)
```
    Description copied from class: SQLStatement
    
    Method to form a join to the specified table using the provided mappings and applying the provided join condition (rather than generating one from the source/target mappings). This is used with JPQL where we allow two root entities to be joined using a provide "ON" condition.
    
    Overrides:
    
    join in class SQLStatement
    
    Parameters:
    
    joinType - Type of join.
    
    sourceTable - SQLTable for the source (null implies primaryTable)
    
    target - Table to join to
    
    targetAlias - Alias for the target table (if known)
    
    tableGrpName - Name of the table group for the target (null implies a new group)
    
    joinCondition - On clause for the join
    
    applyToUnions - Whether to apply to any unioned statements (only applies to SELECT statements)
    
    Returns:
    
    SQLTable for the target
  - removeCrossJoin
```
public String removeCrossJoin(SQLTable targetSqlTbl)
```
    Description copied from class: SQLStatement
    
    Method to remove a cross join for the specified table (if joined via cross join). Also removes the table from the list of tables. This is called where we have bound a variable via a CROSS JOIN (in the absence of better information) and found out later it could become an INNER JOIN. If the supplied table is not joined via a cross join then does nothing.
    
    Overrides:
    
    removeCrossJoin in class SQLStatement
    
    Parameters:
    
    targetSqlTbl - The table to drop the cross join for
    
    Returns:
    
    The removed alias
  - whereAnd
```
public void whereAnd(BooleanExpression expr,
                     boolean applyToUnions)
```
    Method to add an AND condition to the WHERE clause.
    
    Overrides:
    
    whereAnd in class SQLStatement
    
    Parameters:
    
    expr - The condition
    
    applyToUnions - whether to apply this and to any UNIONs in the statement
  - whereOr
```
public void whereOr(BooleanExpression expr,
                    boolean applyToUnions)
```
    Method to add an OR condition to the WHERE clause.
    
    Overrides:
    
    whereOr in class SQLStatement
    
    Parameters:
    
    expr - The condition
    
    applyToUnions - Whether to apply to unions

Class SelectStatement

Nested Class Summary

Field Summary

Fields inherited from class org.datanucleus.store.rdbms.sql.SQLStatement

Constructor Summary

Method Summary

Methods inherited from class org.datanucleus.store.rdbms.sql.SQLStatement

Methods inherited from class java.lang.Object

Field Detail

allowUnions

unions

distinct

selectedItems

aggregated

groupingExpressions

having

orderingExpressions

orderingDirections

orderNullDirectives

rangeOffset

rangeCount

Constructor Detail

SelectStatement

SelectStatement

SelectStatement

SelectStatement

Method Detail

isDistinct

setDistinct

getNumberOfSelects

select

select

select

select

selectItem

addAndConditionToJoinForTable

addGroupingExpression

setHaving

setOrdering

setOrdering

setRange

getSQLText

getSqlForJoins

generateOrderingStatement

addOrderComponent

addOrderingColumnsToSelect

setAllowUnions

getNumberOfUnions

getUnions

union

allUnionsForSamePrimaryTable

join

join

removeCrossJoin

whereAnd

whereOr