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SQL Minimum Grammar

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This section describes the minimum SQL syntax that an ODBC driver must support. The syntax described in this section is a subset of the Entry level syntax of SQL-92.

An application can use any of the syntax in this section and be assured that any ODBC-compliant driver will support that syntax. To determine whether additional features of SQL-92 not in this section are supported, the application should call SQLGetInfo with the SQL_SQL_CONFORMANCE information type. Even if the driver does not conform to any SQL-92 conformance level, an application can still use the syntax described in this section. If a driver conforms to a SQL-92 level, on the other hand, it supports all syntax included in that level. This includes the syntax in this section because the minimum grammar described here is a pure subset of the lowest SQL-92 conformance level. Once the application knows the SQL-92 level supported, it can determine whether a higher-level feature is supported (if any) by calling SQLGetInfo with the individual information type corresponding to that feature.

Drivers that work only with read-only data sources might not support those parts of the grammar included in this section that deal with changing data. An application can determine if a data source is read-only by calling SQLGetInfo with the SQL_DATA_SOURCE_READ_ONLY information type.

Statement

create-table-statement ::=

CREATE TABLE base-table-name

(column-identifier data-type [,column-identifier data-type]...)

Important

As a data-type in a create-table-statement, applications must use a data type from the TYPE_NAME column of the result set returned by SQLGetTypeInfo.

delete-statement-searched ::=

DELETE FROM table-name [WHERE search-condition]

drop-table-statement ::=

DROP TABLE base-table-name

insert-statement ::=

INSERT INTO table-name [( column-identifier [, column-identifier]...)] VALUES (insert-value[, insert-value]... )

select-statement ::=

SELECT [ALL | DISTINCT] select-list

FROM table-reference-list

[WHERE search-condition]

[order-by-clause]

statement ::= create-table-statement

| delete-statement-searched

| drop-table-statement

| insert-statement

| select-statement

| update-statement-searched

update-statement-searched

UPDATE table-name

SET column-identifier = {expression | NULL }

[, column-identifier = {expression | NULL}]...

[WHERE search-condition]

This section contains the following topics.