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Statistics Used by the PlannerManual ChaptersPG1814.2. Statistics Used by the PlannerStatistics Used by the Planner Steps to Upgrade a Cascaded Logical Replication ClusterManual ChaptersPG1829.13.3.2. Steps to Upgrade a Cascaded Logical Replication Cluster Let's say we have a cascaded logical replication setup node1->node2->node3. Here node2 is subscribing the changes from node…Steps to Upgrade a Cascaded Logical Replication Cluster Steps to Upgrade a Two-node Circular Logical Replication ClusterManual ChaptersPG1829.13.3.3. Steps to Upgrade a Two-node Circular Logical Replication Cluster Let's say we have a circular logical replication setup node1->node2 and node2->node1. Here node2 is subscribing th…Steps to Upgrade a Two-node Circular Logical Replication Cluster Steps to Upgrade a Two-node Logical Replication ClusterManual ChaptersPG1829.13.3.1. Steps to Upgrade a Two-node Logical Replication Cluster Let's say publisher is in node1 and subscriber is in node2. The subscriber node2 has a subscription sub1_node1_node2 which …Steps to Upgrade a Two-node Logical Replication Cluster Stop WordsManual ChaptersPG1812.6.1. Stop Words Stop words are words that are very common, appear in almost every document, and have no discrimination value. Therefore, they can be ignored in the context of full text se…Stop Words Stopping the ServerManual ChaptersPG18Stopping the Server To stop the server, use: $ pg_ctl stop The -m option allows control over how the server shuts down: $ pg_ctl stop -m smartStopping the Server Storage ParametersManual ChaptersPG18Storage Parameters The WITH clause can specify storage parameters for tables, and for indexes associated with a UNIQUE, PRIMARY KEY, or EXCLUDE constraint. Storage parameters for indexes are…Storage Parameters Stream Abort CallbackManual ChaptersPG1847.6.4.16. Stream Abort Callback The required stream_abort_cb callback is called to abort a previously streamed transaction. typedef void (*LogicalDecodeStreamAbortCB) (struct LogicalDecodin…Stream Abort Callback Stream Change CallbackManual ChaptersPG1847.6.4.19. Stream Change Callback The required stream_change_cb callback is called when sending a change in a block of streamed changes (demarcated by stream_start_cb and stream_stop_cb call…Stream Change Callback Stream Commit CallbackManual ChaptersPG1847.6.4.18. Stream Commit Callback The required stream_commit_cb callback is called to commit a previously streamed transaction. typedef void (*LogicalDecodeStreamCommitCB) (struct LogicalDec…Stream Commit Callback Stream Message CallbackManual ChaptersPG1847.6.4.20. Stream Message Callback The optional stream_message_cb callback is called when sending a generic message in a block of streamed changes (demarcated by stream_start_cb and stream_s…Stream Message Callback Stream Prepare CallbackManual ChaptersPG1847.6.4.17. Stream Prepare Callback The stream_prepare_cb callback is called to prepare a previously streamed transaction as part of a two-phase commit. This callback is required when the out…Stream Prepare Callback Stream Start CallbackManual ChaptersPG1847.6.4.14. Stream Start Callback The required stream_start_cb callback is called when opening a block of streamed changes from an in-progress transaction. typedef void (*LogicalDecodeStreamS…Stream Start Callback Stream Stop CallbackManual ChaptersPG1847.6.4.15. Stream Stop Callback The required stream_stop_cb callback is called when closing a block of streamed changes from an in-progress transaction. typedef void (*LogicalDecodeStreamSto…Stream Stop Callback Stream Truncate CallbackManual ChaptersPG1847.6.4.21. Stream Truncate Callback The optional stream_truncate_cb callback is called for a TRUNCATE command in a block of streamed changes (demarcated by stream_start_cb and stream_stop_cb…Stream Truncate Callback Streaming of Large Transactions for Logical DecodingManual ChaptersPG1847.9. Streaming of Large Transactions for Logical Decoding The basic output plugin callbacks (e.g., begin_cb, change_cb, commit_cb and message_cb) are only invoked when the transaction actua…Streaming of Large Transactions for Logical Decoding Streaming ReplicationManual ChaptersPG1826.2.5. Streaming Replication Streaming replication allows a standby server to stay more up-to-date than is possible with file-based log shipping. The standby connects to the primary, which …Streaming Replication Streaming Replication and RecoveryManual ChaptersPG18E.6.3.1.7. Streaming Replication and Recovery Allow inactive replication slots to be automatically invalidated using server variable idle_replication_slot_timeout (Nisha Moond, Bharath Rupir…Streaming Replication and Recovery Streaming Replication ProtocolManual ChaptersPG1854.4. Streaming Replication Protocol To initiate streaming replication, the frontend sends the replication parameter in the startup message. A Boolean value of true (or on, yes, 1) tells the…Streaming Replication Protocol Streaming Replication Protocol InterfaceManual ChaptersPG1847.3. Streaming Replication Protocol Interface The commands CREATE_REPLICATION_SLOT slot_name LOGICAL output_plugin DROP_REPLICATION_SLOT slot_name [ WAIT ] START_REPLICATION SLOT slot_name …Streaming Replication Protocol Interface Strict and Lax ModesManual ChaptersPG189.16.2.2. Strict and Lax Modes When you query JSON data, the path expression may not match the actual JSON data structure. An attempt to access a non-existent member of an object or element …Strict and Lax Modes String Comparison BehaviorManual ChaptersPG18F.9.3. String Comparison Behavior citext performs comparisons by converting each string to lower case (as though lower were called) and then comparing the results normally. Thus, for example…String Comparison Behavior String ConstantsManual ChaptersPG184.1.2.1. String Constants A string constant in SQL is an arbitrary sequence of characters bounded by single quotes ('), for example 'This is a string'. To include a single-quote character wi…String Constants String Constants with C-Style EscapesManual ChaptersPG184.1.2.2. String Constants with C-Style Escapes PostgreSQL also accepts “escape” string constants, which are an extension to the SQL standard. An escape string constant is specified by writin…String Constants with C-Style Escapes String Constants with Unicode EscapesManual ChaptersPG184.1.2.3. String Constants with Unicode Escapes PostgreSQL also supports another type of escape syntax for strings that allows specifying arbitrary Unicode characters by code point. A Unicode…String Constants with Unicode Escapes String Functions and OperatorsManual ChaptersPG189.4. String Functions and Operators This section describes functions and operators for examining and manipulating string values. Strings in this context include values of the types character…String Functions and Operators struct sqlname StructureManual ChaptersPG1834.7.2.1.3. struct sqlname Structure A struct sqlname structure holds a column name. It is used as a member of the sqlvar_t structure. The definition of the structure is: define NAMEDATALEN …struct sqlname Structure Structure of PL/pgSQLManual ChaptersPG1841.2. Structure of PL/pgSQL Functions written in PL/pgSQL are defined to the server by executing CREATE FUNCTION commands. Such a command would normally look like, say, CREATE FUNCTION somef…Structure of PL/pgSQL Structure of the Bootstrap BKI FileManual ChaptersPG1868.5. Structure of the Bootstrap BKI File The open command cannot be used until the tables it uses exist and have entries for the table that is to be opened. (These minimum tables are pg_cla…Structure of the Bootstrap BKI File StructuresManual ChaptersPG1834.4.4.3.2. Structures A structure whose member names match the column names of a query result, can be used to retrieve multiple columns at once. The structure enables handling multiple colu…Structures Style GuideManual ChaptersPG18J.6. Style GuideStyle Guide SubqueriesManual ChaptersPG187.2.1.3. Subqueries Subqueries specifying a derived table must be enclosed in parentheses. They may be assigned a table alias name, and optionally column alias names (as in Section 7.2.1.2).…Subqueries Subquery ExpressionsManual ChaptersPG189.24. Subquery Expressions This section describes the SQL-compliant subquery expressions available in PostgreSQL. All of the expression forms documented in this section return Boolean (true/…Subquery Expressions SubscribersManual ChaptersPG1829.12.2. Subscribers max_active_replication_origins must be set to at least the number of subscriptions that will be added to the subscriber, plus some reserve for table synchronization. max…Subscribers SubscribersManual ChaptersPG1819.6.4. Subscribers These settings control the behavior of a logical replication subscriber. Their values on the publisher are irrelevant. See Section 29.12 for more details. max_active_repl…Subscribers SubscriptionManual ChaptersPG1829.2. Subscription A subscription is the downstream side of logical replication. The node where a subscription is defined is referred to as the subscriber. A subscription defines the connect…Subscription SubscriptsManual ChaptersPG184.2.3. Subscripts If an expression yields a value of an array type, then a specific element of the array value can be extracted by writing expression[subscript] or multiple adjacent elements…Subscripts Subtransaction Context ManagersManual ChaptersPG1844.7.1. Subtransaction Context Managers Consider a function that implements a transfer between two accounts: CREATE FUNCTION transfer_funds() RETURNS void AS $$ try: plpy.execute("UPDATE acc…Subtransaction Context Managers SubtransactionsManual ChaptersPG1867.3. Subtransactions Subtransactions are started inside transactions, allowing large transactions to be broken into smaller units. Subtransactions can commit or abort without affecting thei…Subtransactions Summary of Changes since Protocol 2.0Manual ChaptersPG1854.10. Summary of Changes since Protocol 2.0 This section provides a quick checklist of changes, for the benefit of developers trying to update existing client libraries to protocol 3.0. The…Summary of Changes since Protocol 2.0