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If this parameter is set to read-write, only a connection in which read-write transactions are accepted by default is considered acceptable. The query SHOW transaction_read_only will be sent upon any successful connection; if it returns on, the connection will be closed. If multiple hosts were specified in the connection string, any remaining servers will be tried just as if the connection attempt had failed. The default value of this parameter, any, regards all connections as acceptable.

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target_session_attrs
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If this parameter is set to read-write, only a connection in which read-write transactions are accepted by default is considered acceptable. The query SHOW transaction_read_only will be sent upon any successful connection; if it returns on, the connection will be closed. If multiple hosts were specified in the connection string, any remaining servers will be tried just as if the connection attempt had failed. The default value of this parameter, any, regards all connections as acceptable.

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target_session_attrs
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target_session_attrs
\n

If this parameter is set to read-write, only a connection in which read-write transactions are accepted by default is considered acceptable. The query SHOW transaction_read_only will be sent upon any successful connection; if it returns on, the connection will be closed. If multiple hosts were specified in the connection string, any remaining servers will be tried just as if the connection attempt had failed. The default value of this parameter, any, regards all connections as acceptable.

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target_session_attrs
\n

This option determines whether the session must have certain properties to be acceptable. It's typically used in combination with multiple host names to select the first acceptable alternative among several hosts. There are six modes:

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\n
\n
any (default)
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\n

any successful connection is acceptable

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read-write
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\n

session must accept read-write transactions by default (that is, the server must not be in hot standby mode and the default_transaction_read_only parameter must be off)

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read-only
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session must not accept read-write transactions by default (the converse)

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primary
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server must not be in hot standby mode

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standby
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\n

server must be in hot standby mode

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prefer-standby
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first try to find a standby server, but if none of the listed hosts is a standby server, try again in any mode

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target_session_attrs
\n

This option determines whether the session must have certain properties to be acceptable. It's typically used in combination with multiple host names to select the first acceptable alternative among several hosts. There are six modes:

\n
\n
\n
any (default)
\n
\n

any successful connection is acceptable

\n
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read-write
\n
\n

session must accept read-write transactions by default (that is, the server must not be in hot standby mode and the default_transaction_read_only parameter must be off)

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read-only
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session must not accept read-write transactions by default (the converse)

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primary
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server must not be in hot standby mode

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standby
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server must be in hot standby mode

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prefer-standby
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first try to find a standby server, but if none of the listed hosts is a standby server, try again in any mode

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Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults."]}, {"title": "Environment variable evidence", "paragraphs": ["PGTARGETSESSIONATTRS behaves the same as the target_session_attrs connection parameter."]}], "signature": "target_session_attrs", "documented": true, "description": ["This option determines whether the session must have certain properties to be acceptable. 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target_session_attrs
\n

This option determines whether the session must have certain properties to be acceptable. It's typically used in combination with multiple host names to select the first acceptable alternative among several hosts. There are six modes:

\n
\n
\n
any (default)
\n
\n

any successful connection is acceptable

\n
\n
read-write
\n
\n

session must accept read-write transactions by default (that is, the server must not be in hot standby mode and the default_transaction_read_only parameter must be off)

\n
\n
read-only
\n
\n

session must not accept read-write transactions by default (the converse)

\n
\n
primary
\n
\n

server must not be in hot standby mode

\n
\n
standby
\n
\n

server must be in hot standby mode

\n
\n
prefer-standby
\n
\n

first try to find a standby server, but if none of the listed hosts is a standby server, try again in any mode

\n
\n
\n
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", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-TARGET-SESSION-ATTRS", "source_option": {"keyword": "target_session_attrs", "declaration": "\"target_session_attrs\", \"PGTARGETSESSIONATTRS\", DefaultTargetSessionAttrs, NULL, \"Target-Session-Attrs\", \"\", 15, offsetof(struct pg_conn, target_session_attrs)", "environment": "PGTARGETSESSIONATTRS", "source_notes": [], "compiled_default_expression": "DefaultTargetSessionAttrs"}, "comparison_data": {"keyword": "target_session_attrs", "definition": "This option determines whether the session must have certain properties to be acceptable. It's typically used in combination with multiple host names to select the first acceptable alternative among several hosts. 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target_session_attrs
\n

This option determines whether the session must have certain properties to be acceptable. It's typically used in combination with multiple host names to select the first acceptable alternative among several hosts. There are six modes:

\n
\n
\n
any (default)
\n
\n

any successful connection is acceptable

\n
\n
read-write
\n
\n

session must accept read-write transactions by default (that is, the server must not be in hot standby mode and the default_transaction_read_only parameter must be off)

\n
\n
read-only
\n
\n

session must not accept read-write transactions by default (the converse)

\n
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primary
\n
\n

server must not be in hot standby mode

\n
\n
standby
\n
\n

server must be in hot standby mode

\n
\n
prefer-standby
\n
\n

first try to find a standby server, but if none of the listed hosts is a standby server, try again in any mode

\n
\n
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any (default)
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any successful connection is acceptable

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session must accept read-write transactions by default (that is, the server must not be in hot standby mode and the default_transaction_read_only parameter must be off)

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session must not accept read-write transactions by default (the converse)

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server must not be in hot standby mode

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server must be in hot standby mode

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first try to find a standby server, but if none of the listed hosts is a standby server, try again in any mode

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target_session_attrs
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any (default)
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any successful connection is acceptable

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session must accept read-write transactions by default (that is, the server must not be in hot standby mode and the default_transaction_read_only parameter must be off)

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read-only
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session must not accept read-write transactions by default (the converse)

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primary
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server must not be in hot standby mode

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standby
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server must be in hot standby mode

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prefer-standby
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first try to find a standby server, but if none of the listed hosts is a standby server, try again in any mode

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any (default)
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any successful connection is acceptable

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session must accept read-write transactions by default (that is, the server must not be in hot standby mode and the default_transaction_read_only parameter must be off)

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session must not accept read-write transactions by default (the converse)

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primary
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server must not be in hot standby mode

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server must be in hot standby mode

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first try to find a standby server, but if none of the listed hosts is a standby server, try again in any mode

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target_session_attrs
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any (default)
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any successful connection is acceptable

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session must accept read-write transactions by default (that is, the server must not be in hot standby mode and the default_transaction_read_only parameter must be off)

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session must not accept read-write transactions by default (the converse)

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primary
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server must not be in hot standby mode

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standby
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server must be in hot standby mode

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prefer-standby
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