ClickHouse/src/Storages/transformQueryForExternalDatabase.h

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#pragma once
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#include <common/types.h>
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#include <Core/NamesAndTypes.h>
#include <Parsers/IdentifierQuotingStyle.h>
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#include <Storages/SelectQueryInfo.h>
#include <Interpreters/Context_fwd.h>
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namespace DB
{
class IAST;
/** For given ClickHouse query,
* creates another query in a form of
*
* SELECT columns... FROM db.table WHERE ...
*
* where 'columns' are all required columns to read from "left" table of original query,
* and WHERE contains subset of (AND-ed) conditions from original query,
* that contain only compatible expressions.
*
* Compatible expressions are comparisons of identifiers, constants, and logical operations on them.
*/
String transformQueryForExternalDatabase(
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const SelectQueryInfo & query_info,
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const NamesAndTypesList & available_columns,
IdentifierQuotingStyle identifier_quoting_style,
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const String & database,
const String & table,
ContextPtr context);
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}