CREATE FUNCTION defines a new function. CREATE OR REPLACE FUNCTION will either create a new function, or replace an existing definition. To be able to define a function, the user
The first line uses PostgreSQL's CREATE OR REPLACE FUNCTION statement to create the function. The name of the function is fib. The CREATE OR REPLACE FUNCTION statement is more useful in practice than the simple CREATE FUNCTION statement...
Thefib_cached()function defined from lines 6-28 introduces quite a bit more syntax. The first line with something new is line five'sDECLAREstatement. As you may have ascertained by the previous discussion of argument aliases, this statement introduces a block for declaring variables for use in ...
{ CREATE | ALL [ PRIVILEGES ] } ON TABLESPACE tablespace_name [, ...] TO { username | GROUP group_name | PUBLIC } [, ...] [ WITH GRANT OPTION ] GRANT { EXECUTE | ALL [ PRIVILEGES ] } ON FUNCTION func_name ([type, ...]) [, ...] TO { username | GROUP group_name | ...
Command:CREATETRIGGERDescription:define anewtriggerSyntax:CREATE[CONSTRAINT]TRIGGERname{BEFORE|AFTER|INSTEADOF}{event[OR...]}ONtable_name[FROMreferenced_table_name]{NOTDEFERRABLE|[DEFERRABLE]{INITIALLYIMMEDIATE|INITIALLYDEFERRED}}[FOR[EACH]{ROW|STATEMENT}][WHEN(condition)]EXECUTEPROCEDUREfunction_name(argume...
-- Alternative syntax for string literal: CREATE FUNCTION one() RETURNS integer AS ' SELECT 1 AS result; ' LANGUAGE SQL; SELECT one(); -- 返回空 CREATE FUNCTION clean_emp() RETURNS void AS ' DELETE FROM emp WHERE salary < 0;
Syntax: [ WITH [ RECURSIVE ] with_query [, ...] ] SELECT [ ALL | DISTINCT [ ON ( expression [, ...] ) ] ] [ * | expression [ [ AS ] output_name ] [, ...] ] [ FROM from_item [, ...] ] [ WHERE condition ] ...
variables show help on special variables \h [NAME] help on syntax of SQL commands, * for all commandsQuery Buffer \e [FILE] [LINE] edit the query buffer (or file) with external editor \ef [FUNCNAME [LINE]] edit function definition with external editor...Informational (o...
CREATE OR REPLACE FUNCTION normalize(x int) RETURNS int AS $$ BEGIN RETURN x; END; $$ LANGUAGE plpgsql; postgres=# ERROR: syntax error at or near "normalize" postgres=# LINE 1: CREATE OR REPLACE FUNCTION fn2(normalize int) RETURNS int AS... 解析过程分析 已创建失败的函数normalize为例,分...
Datumcomplex_in(PG_FUNCTION_ARGS) {char*str=PG_GETARG_CSTRING(0); double x, y; Complex *result;if(sscanf(str," ( %lf , %lf )", &x, &y) !=2)ereport(ERROR, (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),errmsg("invalid input syntax for complex: \"%s\"",str))); ...