本文将介绍PostgreSQL以下数据类型 整数类型(integer types) 任意精度类型(arbitrary precision numbers) 浮点数类型(floating-point types) 序列类型(serial types) 金额类型(monetary types) 字符类型(character types) 二进制数据类型(binary data types) 日期/时间类型(date/time types) 布尔类型(boolean type) 枚举类...
DATA_TYPE: The datatype of the argument DATA_LEVEL: The nesting depth of the argument for composite types (for example, if one of your arguments’ datatypes is a record, USER_ARGUMENTS will have a row for this argument with a DATA_LEVEL of 0 and then a row for each field in the rec...
(parsetree=0x1f985a0, query_string=0x1f971c8 "select s.*\nfrom t_student s\nwhere s.sdept='IS'\nor---Type <return> to continue, or q <return> to quit--- der by s.sno desc \nlimit 2;", paramTypes=0x0, numParams=0, queryEnv=0x0) at postgres.c:666 #10 0x00000000008c...
序列不应拷贝,应当为每一张复制的表单独创建一个新的序列。 搞清楚这些问题后接下来看看PostgreSQL的相关支持能为我们实现什么,首先看一下CREATE TABLE AS,官方是这样描述的: 如上图所示,CREATE TABLE AS主要做两件事情,分别是建表(CREATE DATA)和填充数据(FILL DATA),下面我们就通过CREATE TABLE AS复制一张表试...
likely give you a wrong result.attention to rounding. Do not use PostgreSQL’s round function, which is not SQL standard and wouldplus 20%. Return the invoice ID. Keep in mind the datatype of ”amount” in invoices and pay special(03) Find invoices that have been taxed. The amount of...
PostgreSQL一个事务中可以包含DML, DDL, DCL。 Begin; Drop table t; Rollback; t表还在,可以放在事务里面。 除了以下 create tablespace create database 使用concurrently并行创建索引 其他未尽情况略 (Oracle执行DDL前自动将前面的未提交的事务提交,所以Oracle不支持在事务中执行DDL语句) 九、Query 1、JOIN T1 CRO...
User-defined data types can be defined by a standard, by an implementation, or by an application. A constructed type is specified using one of SQL's data type constructors, ARRAY, REF, and ROW. The type is either an array type, a reference type or a row type, according to whether it...
Oftentimes you will want to generate dynamic commands inside your PL/pgSQL functions, that is, commands that will involve different tables or different data types each time they are executed. EXECUTE command-string[INTO[STRICT] target ] [USINGexpression [, ... ] ]; ...
带有(pd_table, conn, keys, data_iter)参数的函数: 可以根据特定的后台语言特性,实现高性能的插入方法 下面的例子是PostgreSQL的COPY语句 # Alternative to_sql() *method* for DBs that support COPY FROM import csv from io import StringIO def psql_insert_copy(table, conn, keys, data_iter): ...