使用准则进行条件查询--1.3.运行查询前输入参数
使用准则进行条件查询--1.3.运行查询前输入参数
3.运行查询前输入参数 参数查询可以显示一个或多个提示参数值(准则)的预定义对话框。 在要作为参数使用的每一字段下的“准则”单元格中,在方括号内键入相应的提示。此查询运行时,Microsoft Access 将显示该提示。
在这个设计视图中,在日期字段添写了准则:[请输入要查询的日期:]
当查询运行时,先弹出一个对话框,
要求输入参数值,提示信息就是准则中[ ]内的文本。
如果按取消键,查询将终止,不出现查询结果。
查询的运行结果,因为输入的参数为“99-7-15”,
所以只列出了运输日期为1999年7月15日的记录。 在准则中还可以输入更复杂的表达式,比如对于显示日期的字段,在准则中填写“Between [请键入开始日期] And [请键入结束日期]”,运行时将连续出现两个对话框,分别要求输入开始日期和结束日期,结果将显示介于这两个日期之间的记录。

Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

AI Hentai Generator
Generate AI Hentai for free.

Hot Article

Hot Tools

Notepad++7.3.1
Easy-to-use and free code editor

SublimeText3 Chinese version
Chinese version, very easy to use

Zend Studio 13.0.1
Powerful PHP integrated development environment

Dreamweaver CS6
Visual web development tools

SublimeText3 Mac version
God-level code editing software (SublimeText3)

Hot Topics



The article discusses using MySQL's ALTER TABLE statement to modify tables, including adding/dropping columns, renaming tables/columns, and changing column data types.

InnoDB's full-text search capabilities are very powerful, which can significantly improve database query efficiency and ability to process large amounts of text data. 1) InnoDB implements full-text search through inverted indexing, supporting basic and advanced search queries. 2) Use MATCH and AGAINST keywords to search, support Boolean mode and phrase search. 3) Optimization methods include using word segmentation technology, periodic rebuilding of indexes and adjusting cache size to improve performance and accuracy.

Article discusses configuring SSL/TLS encryption for MySQL, including certificate generation and verification. Main issue is using self-signed certificates' security implications.[Character count: 159]

Article discusses popular MySQL GUI tools like MySQL Workbench and phpMyAdmin, comparing their features and suitability for beginners and advanced users.[159 characters]

Article discusses strategies for handling large datasets in MySQL, including partitioning, sharding, indexing, and query optimization.

The article discusses dropping tables in MySQL using the DROP TABLE statement, emphasizing precautions and risks. It highlights that the action is irreversible without backups, detailing recovery methods and potential production environment hazards.

MySQL supports four index types: B-Tree, Hash, Full-text, and Spatial. 1.B-Tree index is suitable for equal value search, range query and sorting. 2. Hash index is suitable for equal value searches, but does not support range query and sorting. 3. Full-text index is used for full-text search and is suitable for processing large amounts of text data. 4. Spatial index is used for geospatial data query and is suitable for GIS applications.

The article discusses creating indexes on JSON columns in various databases like PostgreSQL, MySQL, and MongoDB to enhance query performance. It explains the syntax and benefits of indexing specific JSON paths, and lists supported database systems.
