Package org.sqlproc.engine.plugin

Interface SqlFromToPlugin

All Superinterfaces:

Modifiers

All Known Implementing Classes:

DefaultSqlPlugins

public interface SqlFromToPlugin
extends Modifiers

The SQL Processor plugin devoted to the FROM-TO SQL construction. The primary usage is to support the pagination. There are utilized the patterns from the SqlFeature. These pattern have to be combined with the original SQL query, the limit and the offset in the next way:

• $S is the full original query
• $s is the original query without the token select
• $F is 1-based from rowid (=offset)
• $f is 0-based from rowid (offset)
• $M is the max number of returned rows
• $m is the max rowid of returned rows

Author:

Vladimir Hudec

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static class	SqlFromToPlugin.LimitType	The characteristic of FROM and TO restrictions used in SqlQuery.list(SqlRuntimeContext).

Field Summary

Fields inherited from interface org.sqlproc.engine.plugin.Modifiers

MODIFIER_ANY, MODIFIER_ANYSET, MODIFIER_CALL, MODIFIER_DISCRIMINATOR, MODIFIER_EMPTY, MODIFIER_GTYPE, MODIFIER_ID, MODIFIER_IDENTITY_GENERATOR, MODIFIER_IDENTITY_SELECT, MODIFIER_NOTEMPTY, MODIFIER_NOTNULL, MODIFIER_NULL, MODIFIER_SEQUENCE, MODIFIER_TYPE

Method Summary

Modifier and Type	Method	Description
SqlFromToPlugin.LimitType	limitQuery(SqlRuntimeContext runtimeCtx, String queryString, StringBuilder queryResult, Integer firstResult, Integer maxResults, boolean ordered)	Used to construct the FROM-TO SQL.

Method Detail

limitQuery

SqlFromToPlugin.LimitType limitQuery(SqlRuntimeContext runtimeCtx,
                                     String queryString,
                                     StringBuilder queryResult,
                                     Integer firstResult,
                                     Integer maxResults,
                                     boolean ordered)

Used to construct the FROM-TO SQL.

Parameters:

runtimeCtx - the public runtime context

queryString - the original ANSI SQL

queryResult - the final ANSI SQL reflected FROM and TO restrictions

firstResult - The first SQL execution output row to be returned in the case we need to skip some rows in the result set. The primary usage is to support the pagination.

maxResults - The max number of SQL execution output rows, which can be returned in the result list. The primary usage is to support the pagination.

ordered - the SQL output is sorted

Returns:

the characteristic of FROM and TO restrictions used in SqlQuery.list(SqlRuntimeContext)