TParams.ParseSQL function

Member of TParamspublicIn unit DB

Parse SQL statement, replacing parameter names with SQL parameter placeholders.

Declaration

pascal

function ParseSQL(const SQL: string; DoCreate: Boolean): string
 ; overload
function ParseSQL(const SQL: string; DoCreate: Boolean; 
 EscapeSlash: Boolean; EscapeRepeat: Boolean; 
 ParameterStyle: TParamStyle): string; overload
function ParseSQL(const SQL: string; DoCreate: Boolean; 
 EscapeSlash: Boolean; EscapeRepeat: Boolean; 
 ParameterStyle: TParamStyle; 
 out ParamBinding: TParamBinding): string; overload
function ParseSQL(const SQL: string; DoCreate: Boolean; 
 EscapeSlash: Boolean; EscapeRepeat: Boolean; 
 ParameterStyle: TParamStyle; 
 out ParamBinding: TParamBinding; 
 out ReplaceString: string): string; overload
function ParseSQL(const SQL: string; Options: TSQLParseOptions; 
 ParameterStyle: TParamStyle; 
 out ParamBinding: TParamBinding; MacroChar: char; 
 out ReplaceString: string): string

Arguments

`SQL`	SQL statement to scan for parameter names.
`DoCreate`	Set to `True` if `TParam` instances must be created for the found parameters.
`EscapeSlash`	`True` if the backslash character acts as an escape token.
`EscapeRepeat`	`True` if quotes are escaped by specifying them two times.
`ParameterStyle`	SQL Placeholder style.
`ParamBinding`	On return, filled with indexes of `TParam` instances corresponding to the placeholders.
`ReplaceString`	Placeholder string.
`Options`	Contains the parser options enabled when parsing the SQL statement.
`MacroChar`	Character which triggers expansion of a named macro in the SQL statement.

Function result

SQL statement with parameter names replaced with placeholders.

Description

ParseSQl parses the SQL statement for parameter names in the form :ParamName. It replaces them with a SQL parameter placeholder. If DoCreate is True then a TParam instance is added to the collection with the found parameter name.

The parameter placeholder is determined by the ParameterStyle property, which can have the following values:

psInterbase: Parameters are specified by a ? character.
psPostgreSQL: Parameters are specified by a $N character.
psSimulated: Parameters are specified by a $N character.

psInterbase is the default.

If the EscapeSlash parameter is True, then backslash characters are used to quote the next character in the SQL statement. If it is False, the backslash character is regarded as a normal character.

If the EscapeRepeat parameter is True (the default) then embedded quotes in string literals are escaped by repeating themselves. If it is false then they should be quoted with backslashes.

ParamBinding, if specified, is filled with the indexes of the parameter instances in the parameter collection: for each SQL parameter placeholder, the index of the corresponding TParam instance is returned in the array.

ReplaceString, if specified, contains the placeholder used for the parameter names (by default, $). It has effect only when ParameterStyle equals psSimulated.

The function returns the SQL statement with the parameter names replaced by placeholders.

TParams.ParseSQL function

Declaration

Arguments

Function result

Description

See also