The overall execution cycle consists of a parse step, which creates a prepared statement from a textual query string; a bind step, which creates a portal given a prepared statement and values for any needed parameters; and an execute step that runs a portal's query. In the case of a quer...
\w FILE write query buffer to file Input/Output \copy ... perform SQL COPY with data stream to the client host \echo [STRING] write string to standard output \i FILE execute commands from file \o [FILE] send all query results to file or |pipe \qecho [STRING] write string to query...
EXECUTE plan_name [ (parameter [, ...] ) ]EXPLAIN显示一个语句的执行规划。EXPLAIN [ ANALYZE ] [ VERBOSE ] statementFETCH用游标从查询中抓取行。FETCH [ direction { FROM | IN } ] cursor_namedirection 可以是以下选项之一:NEXT PRIOR FIRST LAST ABSOLUTE count RELATIVE count count ALL FORWARD ...
port="your_port") # 创建游标对象 cur = conn.cursor() # 准备预处理语句 cur.prepare("SELECT * FROM your_table WHERE column = %s") # 准备参数 param = "your_string" # 执行查询 cur.execute("EXECUTE your_query (%s)", (param,)) # 获取查询结果 result = cur.fetchall() # 关闭游...
;的入口函数ExecuteCallStmt:入参为CallStmt,函数中将CallStmt中的参数列表(可能是值、可能是表达式)赋值给fcinfo,然后通过PG函数框架进入plpgsql堆栈中,给对应入参的Dataums赋值。(下一篇介绍CallStmt中的args在哪里构造) 入参有两组args,一组是语法解析直接生成的funccall;一组是经过优化器的funcexpr:...
/* And now back to C string */ c_sql=text_to_cstring(DatumGetTextPP(t_sql)); execute_sql_string(c_sql); } PG_CATCH(); { creating_extension=false; CurrentExtensionObject=InvalidOid; PG_RE_THROW(); } PG_END_TRY(); creating_extension=false; ...
EXECUTE PROCEDURE strig();ANALYZE exp;INSERT INTO exp VALUES (1,1), (2,3),(4,5),(6,7),(8,9);DELETE FROM exp;INSERT INTO exp VALUES (1,1);ALTER TABLE exp SET (autovacuum_vacuum_threshold= 1);ALTER TABLE exp SET (autovacuum_analyze_threshold= 1);这里 Vacuum exp调用sfunc ( )将...
Execute a SQL SELECT query with the table name as a dynamic variable using bind variables. This query returns the number of employees under a manager with a specific ID. DO $$DECLARE Tabname varchar(30) := 'employees'; num integer := 1; cnt integer; BEGIN EXECUTE format('...
{ statement.execute(scanner.nextLine()); } /* Todo todo = new Todo(1L, "configuration", "congratulations, you have set up JDBC correctly!", true); insertData(todo, connection); todo = readData(connection); todo.setDetails("congratulations, you have updated data!"); updateData(todo, ...
execute(): Return true if the first object of the query is a ResultSet object. You can get the ResultSet by calling the method getResultSet(). executeQuery(): Return only one ResultSet object. executeUpdate(): Return the number of rows affected by the statement. Typically, you use this...