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32 lines
978 B
C++
32 lines
978 B
C++
#pragma once
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#include <TableFunctions/ITableFunction.h>
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namespace DB
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{
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/* remote ('address', db, table) - creates a temporary StorageDistributed.
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* To get the table structure, a DESC TABLE request is made to the remote server.
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* For example
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* SELECT count() FROM remote('example01-01-1', merge, hits) - go to `example01-01-1`, in the merge database, the hits table.
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* An expression that generates a set of shards and replicas can also be specified as the host name - see below.
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* Also, there is a cluster version of the function: cluster('existing_cluster_name', 'db', 'table')
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*/
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class TableFunctionRemote : public ITableFunction
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{
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public:
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explicit TableFunctionRemote(const std::string & name_ = "remote");
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std::string getName() const override { return name; }
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private:
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StoragePtr executeImpl(const ASTPtr & ast_function, const Context & context) const override;
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std::string name;
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bool is_cluster_function;
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std::string help_message;
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};
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}
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