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https://docwiki.embarcadero.com/RADStudio/Rio/en/Master-Detail_Relationship_(M/D)

https://docwiki.embarcadero.com/CodeExamples/Sydney/en/FireDAC.TFDQuery.Indices_Sample

The identifier substitution escape sequence allows abstracting from DBMS-specific identifier quoting rules. For more details, see "Object Names". The syntax is:

Format Description
{id <identifier name>} Expands to DBMS-specific quoted identifier syntax.
For example: {id Order Details} -> “Order Details” on Oracle.

https://docwiki.embarcadero.com/RADStudio/Sydney/en/Object_Names_(FireDAC)

FireDAC fully supports quoted object names, including different DBMS quoted characters. To write a quoted name in a SQL in a DBMS independent fashion use the {id <name>} syntax. For example:

SELECT * FROM {id Order Details}
To force TFDTable to quote field names set FormatOptions.QuoteIdentifiers to True.
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The higher the degree, the greater the respect given to the humblest!RAD 11.3

作者：

chc121 ( )	★☆☆☆☆	-
	盒子活跃会员

2021/10/15 12:31:18

2楼：

emailx45：不是太懂，但非常感谢！
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作者：

wg961423 (麦子仲肥)	★☆☆☆☆	-
	盒子活跃会员

2021/10/15 14:19:32

3楼：

FireDAC完全支持带引号的对象名称，包括不同DBMS的引号字符。要以独立于DBMS的方式在SQL中写一个带引号的名字，请使用{id <name>}语法。
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作者：

wg961423 (麦子仲肥)	★☆☆☆☆	-
	盒子活跃会员

2021/10/15 14:27:32

4楼：

即在不同的数据库中，表名可以用不同的符号，如：SQLServer是 [表名] ,MySQL是`表名`，PG是"表名"，FireDac里支持在不同的数据库中用同一个SQL，即全都是用{id 表名}来执行。
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作者：

wg961423 (麦子仲肥)	★☆☆☆☆	-
	盒子活跃会员

2021/10/15 14:34:44

5楼：

SELECT * FROM {id Order Details}
即在SQLServer里会变成：SELECT * FROM [Order Details]
即在MySQL里会变成：SELECT * FROM `Order Details`
即在PG里会变成：SELECT * FROM "Order Details"
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作者：

chc121 ( )	★☆☆☆☆	-
	盒子活跃会员

2021/10/15 18:37:47

6楼：

wg961423 (麦子仲肥)：谢谢！理解了。
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