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Index ¶
Constants ¶
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Variables ¶
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Functions ¶
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Types ¶
type ChdbConn ¶
type ChdbConn interface {
//Query executes the given queryStr in the underlying clickhouse connection, and output the result in the given formatStr
Query(queryStr string, formatStr string) (result ChdbResult, err error)
//Ready returns a boolean indicating if the connections is successfully established.
Ready() bool
//Close the connection and free the underlying allocated memory
Close()
}
func NewConnection
deprecated
NewConnection is the low level function to create a new connection to the chdb server. using NewConnectionFromConnString is recommended.
Deprecated: Use NewConnectionFromConnString instead. This function will be removed in a future version.
Session will keep the state of query. If path is None, it will create a temporary directory and use it as the database path and the temporary directory will be removed when the session is closed. You can also pass in a path to create a database at that path where will keep your data. This is a thin wrapper around the connect_chdb C API. the argc and argv should be like:
- argc = 1, argv = []string{"--path=/tmp/chdb"}
- argc = 2, argv = []string{"--path=/tmp/chdb", "--readonly=1"}
Important:
- There can be only one session at a time. If you want to create a new session, you need to close the existing one.
- Creating a new session will close the existing one.
- You need to ensure that the path exists before creating a new session. Or you can use NewConnectionFromConnString.
func NewConnectionFromConnString ¶ added in v1.9.0
NewConnectionFromConnString creates a new connection to the chdb server using a connection string. You can use a connection string to pass in the path and other parameters. Examples:
- ":memory:" (for in-memory database)
- "test.db" (for relative path)
- "file:test.db" (same as above)
- "/path/to/test.db" (for absolute path)
- "file:/path/to/test.db" (same as above)
- "file:test.db?param1=value1¶m2=value2" (for relative path with query params)
- "file::memory:?verbose&log-level=test" (for in-memory database with query params)
- "///path/to/test.db?param1=value1¶m2=value2" (for absolute path)
Connection string args handling:
Connection string can contain query params like "file:test.db?param1=value1¶m2=value2" "param1=value1" will be passed to ClickHouse engine as start up args. For more details, see `clickhouse local --help --verbose` Some special args handling: - "mode=ro" would be "--readonly=1" for clickhouse (read-only mode)
Important:
- There can be only one session at a time. If you want to create a new session, you need to close the existing one.
- Creating a new session will close the existing one.
type ChdbResult ¶
type ChdbResult interface {
// Raw bytes result buffer, used for reading the result of clickhouse query
Buf() []byte
// String rapresentation of the the buffer
String() string
// Lenght in bytes of the buffer
Len() int
// Number of seconds elapsed for the query execution
Elapsed() float64
// Amount of rows returned by the query
RowsRead() uint64
// Amount of bytes returned by the query
BytesRead() uint64
// If the query had any error during execution, here you can retrieve the cause.
Error() error
// Free the query result and all the allocated memory
Free()
}
Source Files