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ArgumentsManual ChaptersPG18Arguments Relation rel Used only as the source of the row descriptor for the row. (Passing a relation rather than a row descriptor is a misfeature.) HeapTuple row row to be modified int ncol…Arguments ArgumentsManual ChaptersPG18Arguments Size size size in bytes of storage to allocateArguments ArgumentsManual ChaptersPG18Arguments void * pointer pointer to existing storage to freeArguments ArgumentsManual ChaptersPG18Arguments const char * command command string int nargs number of input parameters ($1, $2, etc.) Oid * argtypes pointer to an array containing the OIDs of the data types of the parameters i…Arguments ArgumentsManual ChaptersPG18Arguments const char * command command string const SPIPrepareOptions * options struct containing optional arguments Callers should always zero out the entire options struct, then fill which…Arguments ArgumentsManual ChaptersPG18Arguments const char * command command string ParserSetupHook parserSetup Parser hook setup function void * parserSetupArg pass-through argument for parserSetup int cursorOptions integer bit…Arguments ArgumentsManual ChaptersPG18Arguments const char * command command string int nargs number of input parameters ($1, $2, etc.) Oid * argtypes pointer to an array containing the OIDs of the data types of the parametersArguments ArgumentsManual ChaptersPG18Arguments EphemeralNamedRelation enr the ephemeral named relation registry entryArguments ArgumentsManual ChaptersPG18Arguments TriggerData *tdata the TriggerData object passed to a trigger handler function as fcinfo->contextArguments ArgumentsManual ChaptersPG18Arguments int code result codeArguments ArgumentsManual ChaptersPG18Arguments HeapTuple row row to be copied TupleDesc rowdesc descriptor for row (pass the same descriptor each time for most effective caching)Arguments ArgumentsManual ChaptersPG18Arguments SPIPlanPtr plan the prepared statement to be savedArguments ArgumentsManual ChaptersPG18Arguments Portal portal portal containing the cursor FetchDirection direction one of FETCH_FORWARD, FETCH_BACKWARD, FETCH_ABSOLUTE or FETCH_RELATIVE long count number of rows to fetch for FE…Arguments ArgumentsManual ChaptersPG18Arguments Portal portal portal containing the cursor FetchDirection direction one of FETCH_FORWARD, FETCH_BACKWARD, FETCH_ABSOLUTE or FETCH_RELATIVE long count number of rows to move for FET…Arguments ArgumentsManual ChaptersPG18Arguments const char * name the relation registry entry nameArguments Arguments for SQL FunctionsManual ChaptersPG1836.5.1. Arguments for SQL Functions Arguments of an SQL function can be referenced in the function body using either names or numbers. Examples of both methods appear below. To use a name, d…Arguments for SQL Functions armor(), dearmor()Manual ChaptersPG18F.26.3.6. armor(), dearmor() armor(data bytea [ , keys text[], values text[] ]) returns text dearmor(data text) returns bytea These functions wrap/unwrap binary data into PGP ASCII-armor for…armor(), dearmor() Array ConstructorsManual ChaptersPG184.2.12. Array Constructors An array constructor is an expression that builds an array value using values for its member elements. A simple array constructor consists of the key word ARRAY, a…Array Constructors Array Functions and OperatorsManual ChaptersPG189.19. Array Functions and Operators Table 9.56 shows the specialized operators available for array types. In addition to those, the usual comparison operators shown in Table 9.1 are availabl…Array Functions and Operators Array Input and Output SyntaxManual ChaptersPG188.15.6. Array Input and Output Syntax The external text representation of an array value consists of items that are interpreted according to the I/O conversion rules for the array's element …Array Input and Output Syntax Array TypesManual ChaptersPG18Array Types Whenever a user-defined type is created, PostgreSQL automatically creates an associated array type, whose name consists of the element type's name prepended with an underscore, a…Array Types Array Value InputManual ChaptersPG188.15.2. Array Value Input To write an array value as a literal constant, enclose the element values within curly braces and separate them by commas. (If you know C, this is not unlike the C …Array Value Input ArraysManual ChaptersPG188.15. Arrays PostgreSQL allows columns of a table to be defined as variable-length multidimensional arrays. Arrays of any built-in or user-defined base type, enum type, composite type, range…Arrays ArraysManual ChaptersPG1834.4.4.3.1. Arrays There are two use cases for arrays as host variables. The first is a way to store some text string in char[] or VARCHAR[], as explained in Section 34.4.4.1. The second use…Arrays ArraysManual ChaptersPG1834.4.5.1. Arrays Multi-dimensional SQL-level arrays are not directly supported in ECPG. One-dimensional SQL-level arrays can be mapped into C array host variables and vice-versa. However, wh…Arrays Arrays, ListsManual ChaptersPG1844.2.3. Arrays, Lists SQL array values are passed into PL/Python as a Python list. To return an SQL array value out of a PL/Python function, return a Python list: CREATE FUNCTION return_arr(…Arrays, Lists AssignmentManual ChaptersPG1841.5.1. Assignment An assignment of a value to a PL/pgSQL variable is written as: variable { := | = } expression; As explained previously, the expression in such a statement is evaluated by …Assignment Asynchronous Command ProcessingManual ChaptersPG1832.4. Asynchronous Command Processing The PQexec function is adequate for submitting commands in normal, synchronous applications. It has a few deficiencies, however, that can be of importan…Asynchronous Command Processing Asynchronous CommitManual ChaptersPG1828.4. Asynchronous Commit Asynchronous commit is an option that allows transactions to complete more quickly, at the cost that the most recent transactions may be lost if the database should…Asynchronous Commit Asynchronous Execution OptionsManual ChaptersPG18F.38.1.5. Asynchronous Execution Options postgres_fdw supports asynchronous execution, which runs multiple parts of an Append node concurrently rather than serially to improve performance. T…Asynchronous Execution Options Asynchronous NotificationManual ChaptersPG1832.9. Asynchronous Notification PostgreSQL offers asynchronous notification via the LISTEN and NOTIFY commands. A client session registers its interest in a particular notification channel w…Asynchronous Notification Asynchronous OperationsManual ChaptersPG1854.2.7. Asynchronous Operations There are several cases in which the backend will send messages that are not specifically prompted by the frontend's command stream. Frontends must be prepare…Asynchronous Operations AT TIME ZONE and AT LOCALManual ChaptersPG189.9.4. AT TIME ZONE and AT LOCAL The AT TIME ZONE operator converts time stamp without time zone to/from time stamp with time zone, and time with time zone values to different time zones. Ta…AT TIME ZONE and AT LOCAL attributesManual ChaptersPG1835.6. attributes The view attributes contains information about the attributes of composite data types defined in the database. (Note that the view does not give information about table colu…attributes auth_delay — pause on authentication failureManual ChaptersPG18F.2. auth_delay — pause on authentication failure auth_delay causes the server to pause briefly before reporting authentication failure, to make brute-force attacks on database passwords mor…auth_delay — pause on authentication failure Authdata HooksManual ChaptersPG1832.20.1. Authdata Hooks The behavior of the OAuth flow may be modified or replaced by a client using the following hook API: PQsetAuthDataHook # Sets the PGauthDataHook, overriding libpq's h…Authdata Hooks AuthenticationManual ChaptersPG1819.3.3. Authentication authentication_timeout (integer) # Maximum amount of time allowed to complete client authentication. If a would-be client has not completed the authentication protocol…Authentication AuthenticationManual ChaptersPG1826.2.5.1. Authentication It is very important that the access privileges for replication be set up so that only trusted users can read the WAL stream, because it is easy to extract privilege…Authentication Authentication MethodsManual ChaptersPG1820.3. Authentication Methods PostgreSQL provides various methods for authenticating users: Trust authentication, which simply trusts that users are who they say they are. Password authentica…Authentication Methods Authentication ProblemsManual ChaptersPG1820.16. Authentication Problems Authentication failures and related problems generally manifest themselves through error messages like the following: FATAL: no pg_hba.conf entry for host "123…Authentication Problems